Philip Seymour Hoffman had up to 70 bags of heroin inside his Manhattan apartment when he died and more than 20 used syringes according to law enforcement sources - who have launched a city-wide search to catch his drug dealer.
The shocking new details reveal that the Oscar winner - who was found dead on the bathroom floor with a needle sticking out of his arm - had a drug problem that had escalated far beyond what had previously been acknowledged.
And the stark reality of Hoffman's struggle with relapse into addiction were apparently confirmed by his estranged partner, Mimi O'Donnell - who told police that the actor appeared high when she saw him the day before he died.
Indeed, the Oscar winning actor was pictured in an Atlanta bar on January 30 drinking, smoking and repeatedly running in and out of the restroom.
The actor was seen by a diner in a restaurant next door to the Hyatt in downtown Atlanta who said the 46-year-old appeared "sketchy".
He apparently was with a woman at the bar and made "multiple trips" to the bathroom - which alerted the fellow patron's attention.
Apparently Hoffman appeared intoxicated and was later seen at the airport, where he was described as "drunk and disheveled".
O'Donnell told NYPD that she last saw the actor at 2pm on Saturday on the street near to the West Village apartment he was living in.
She told investigators that he appeared to be under the influence of drugs and when she spoke to him again at around 8pm on Saturday, he also sounded high.
On Monday, the NYPD announced a massive citywide search to find the drug dealer or dealers who sold heroin to Philip Seymour Hoffman.
"An internal email went out to all supervisors asking if anyone has had any experience with those brand names of drugs,' a law enforcement source told The New York Post.
"They're going to try to find the source."
The New York Post reported up to 70 bags of heroin were found in Hoffman's apartment.
So far officers have found no evidence of a struggle inside the apartment and it was there his body was found yesterday by close friend and playwright David Bar Katz and British assistant Isabella Wing-Davey, who had been asked to check up on him by Miss O'Donnell.
According to neighbours, O'Donnell was with her children when she rushed to see Hoffman after receiving the terrible news from Wing-Davey and Katz.
Hoffman had apparently arranged to meet them at a nearby playground just a block and a half away.
However when she was told that he had been discovered slumped on the bathroom floor she put her kids in her car, rushed to the West Village apartment and left her children in the running vehicle as she dashed inside, shouting, "I have to see him!"
The medical examiner is to perform an autopsy today to determine the cause of death - with a drugs overdose strongly suspected.
Indeed, authorities searching the fourth floor apartment recovered up to 70 containers of heroin, almost two dozen used syringes as well as anti-anxiety prescriptions that Hoffman didn't appear to have a script for.
According to police sources who spoke to CNN, Hoffman had in his possession the blood-pressure medication clonidine hydrochloride; the addiction-treatment drug buprenorphine; Vyvanse, a drug used to treat attention-deficit (hyperactivity) disorder; hydroxyzine, which can be used to treat anxiety; and methocarbamol, a muscle relaxer.
Police also discovered several other bags containing white powder.
Wing-Davey, who is thought to be 28, holds a BA from Cambridge University in History, and is currently a thesis student in NYU's Tisch School of the Arts Graduate Film Program.
"They were friends, very good friends," said Meg Gibson, who worked with Hoffman and Wing-Davey on Candlesticks - a short film that listed Hoffman as assistant director.
Gibson said that Hoffman was close friends with Wing-Davey's father, Mark Wing-Davey, who chairs the graduate acting department at Tisch - and who also graduated from Cambridge University in 1970.
"She's grown up with him," Gibson said to the New York Daily News about Hoffman's friendship with Isabella Wing-Davey.
"She's been by his side in the last two months with everything he's been working on."
Investigators found eight empty bags stamped with "Ace of Spades" and "Ace of Hearts" inside the actor's Manhattan apartment, according to officials.
They usually contain a lethal mix of heroin laced with fentanyl - an opiate used to soothe the pain of cancer patients.
The card-inspired brand names are among hundreds of stamps used by drug distribution crews to mark products, but they haven't been seen in New York since 2008, according to CNN.
Their lethal contents - also known as "Bud Ice", "Income tax" and "Theraflu" - have been linked to more than 100 deaths in America - with more three dozen deaths in Maryland since September.
Meanwhile, there have been almost 20 related deaths in Pennsylvania in this month alone - with officials estimating a further 22 people dying of heroin-fentanyl overdoses in Rhode Island during the first two weeks of this year, according to the Providence Journal.
Now, police are investigating whether the Oscar award-winning actor may have died after injecting the lethal concoction, according to a source.
Fox News reported a man has come forward claiming they he saw Hoffman buying drugs earlier in the evening.
The passerby claims he saw a "very sweaty" Hoffman withdrawing a large sum of money from an ATM by his home before handing it over to two men wearing messenger bags.
The man reportedly added Hoffman looked "like s***".
Police are now seeking surveillance videos from the bank.
It comes as a haunting last photo has captured 46-year-old Hoffman's torment following his split from his long-term girlfriend, Mimi O'Donnell, in recent months.
Hoffman, who has three elementary-age children with the costume designer, also 46, began renting a $10,000-a-month apartment in Bethune Street in Manhattan's Greenwich Village in October.
The actor's estranged partner was later seen weeping as she entered the property.
On Sunday afternoon, a New York Police Department source told MailOnline: "It is my understanding that Mr Hoffman and his girlfriend were separated."
Mr Hoffman's last public appearance was at the 2014 Sundance Film Festival in January, where he was promoting his movie God's Pocket and also A Most Wanted Man.
He appeared "slightly disheveled and pasty," according to the New York Post.
He had a five o'clock shadow, pale complexion and watery eyes, appearing altogether worn out.
He kept some press commitments, posing on the carpet with his Most Wanted co-stars Rachel McAdams and Willem Dafoe, dressed in baggy clothes.
However, he declined a number of interviews, with his representative telling reporters the actor "needed a minute and didn't feel like coming down yet".
Miss O'Donnell, Mr Hoffman's partner of 14 years, contacted Mr Katz after the actor failed to collect son Cooper, 10, and daughters Tallulah, 7, and Willa, 5, on Sunday morning.
Mr Katz then, with WIng-Davey, went to check on the actor.
Wing-Davey has long had a close relationship with the star after meeting him through her actor father Mark Wing-Davey. Her cell phone has a recorded message asking callers to leave a message for Bella Wing-Davey and Phil.
It was Wing-Davey, a film-maker and writer, who called 911 to report the body. She was then photographed outside the apartment clutching her tan scarf to her face as she spoke to detectives with Mr Katz.
The pair found Mr Hoffman in his underwear on a bathroom floor at apartment 4D, 35 Bethune Street around 11.30am. Allegedly, he had a syringe still in his arm.
Miss O'Donnell was later said to have arrived at the scene but was banned by cops from entering the bathroom, sources said.
After remaining in the apartment all day, the actor's body was finally taken from his home just before 7pm.
It later emerged that the night before he was found dead, Mr Hoffman enjoyed a cheeseburger with friends at one of his favourite restaurants.
In Touch reported the actor dined at West Village restaurant Automatic Slims with two other men from around 7pm. A witness told the magazine he was drinking cranberry and soda and seemed "totally fine".
"The friends he was with seemed like industry people. He had a cheeseburger. He was low-key and friendly and none of them looked like they were looking to party," the witness said.
"He comes in occasionally and just keeps a low profile. He hardly ever drinks. Such a nice guy and very unexpected to hear this news."
On Saturday, employees from one of his favourite places to take his kids - the Chocolate Bar on Eighth Avenue - reported seeing him looking "really happy".
"Everyone seems pretty shaken up," said Kate St. Cyr, 24, the assistant manager told DNAinfo.
"We just saw him yesterday, he was fine," she added. "He's been in a great mood, really happy."
She described Hoffman as a "really sweet man and dad" who would often take his children to the store for ice cream in the summer.
The actor had a specially close bond to his son Cooper who he regularly played weekend basketball with and was often photographed with at Knicks games in Madison Square Garden.
"He seemed to have a really great relationship with his kids," St. Cyr went on. "That's, I think, what's upsetting most of us. We feel really sad for his kids."
However, the next day a neighbour told Fox he had seen the star earlier that day buying tissues and soda at a nearby grocery store.
The neighbour added Hoffman looked "grey" and "not well" before he joined friends for his low-key dinner.
A Most Wanted Man director Anton Corbijn said he was shocked to hear about the death of the actor who just two weeks ago seemed "in a good place".
"We spent some time together only [two] weeks ago and he seemed in a good place despite some issues he had to deal with," Mr Corbijn told the Post.
"He was not only the most gifted actor I ever worked with (and judging by the legacy he leaves behind I am certain I share this with most if not all directors who were fortunate enough to work with him), he had also become an incredibly inspiring and supportive friend.
"I am so terribly sad as I find it impossible to comprehend what happened today and to collect my thoughts properly."
He added: "I have to think about Mimi and the children and [I] wish them much strength coping with the loss of this truly great man as a father and partner."
And today, Seymour Hoffman's college friend and former 3rd Rock From The Sun star, Kristen Johnson posted onto Twitter her tribute, where she acknowledged he was an addict.
"Thank you for all your kind words about Phil. Sadly, after being sober for years & years, he relapsed & has been grappling with his addiction for last few years.
"I wish I could say I was shocked, but all I feel is a mixture of terrible grief, sad resignation & a powerful rage.
"Many, many people die from this disease. Like them, Phil didn't want to die. He fought hard to get clean. He had a family he loved, many friends who adored him & a career he was proud of.
"But addiction doesn't care about that."
Hoffman moved into his new West Village apartment around Christmas time, MailOnline can reveal.
Neighbours said that it was two months at most since he had begun renting the $10,000 a month luxury apartment in New York's West Village.
The timing of his departure gives new insight into the traumatic separation from his family that the actor was going through.
The superintendent of the building, who declined to give his name, said that Hoffman had been there two months.
A man in his 60s who said he was the dog walker however said it was sooner, and six weeks at most.
He said: "I'm in and out of that building 30 times a day and it has been a matter of weeks he's been here."
Earlier, a neighbour at the $4.4 million apartment Mr Hoffman and Miss O'Donnell owned together in Jane Street, less than three blocks away from his rental home, described him as "a troubled soul" to the New York Post.
The couple bought the three-bedroom, 2½-bath apartment in 2008.
"He did not look well recently - like he was out of it," the woman said. "I think him and his woman friend were off and on.
"He lived down here for a long time and was well liked, but everyone knew he had substance-abuse problems," she added.
Just over a week ago, Mr Hoffman was spotted in the audience at the Broadway revival of Waiting for Godot.
Mr Hoffman won the best actor Academy Award for the 2005 film Capote, and has been hailed by the film industry as one of the finest actors of his generation.
The Fairport, New York, native reportedly told TMZ in May that he began taking heroin again after 23 years of being clean. He said he'd progressed from prescription pills to ultimately snorting heroin.
He claimed that he only used heroin for a week before he realized he needed help and checked himself into a detox facility on the East Coast.
He spent 10 days receiving treatment and credited a "great group of friends and family" for helping.
"I saw him last week, and he was clean and sober, his old self," Mr Katz, a screenwriter, told the New York Times. He said he called 911 after finding Mr Hoffman. "I really thought this chapter was over."
Authorities confirmed that the last time the stage and film actor was last seen was around 8pm on Saturday.
The Office of the Chief Medical Examiner is yet to determine the exact cause of death, but law enforcement sources revealed a drug overdose was to blame. Officers found a charred spoon in the kitchen sink, police sources told the New York Post.
A relative told The Post: "We're just really devastated that this could happen."
"There had always been a concern with the business he was in," said Doris Barr, 76, whose son is married to Mr Hoffman's sister.
After Mr Katz called 911, emergency workers rushed to the scene where Mr Hoffman was declared dead on arrival.
Just before 7pm, after CSU investigators, wearing white plastic suits, spent the entire afternoon and much of the evening going in and out of Mr Hoffman's apartment, the crime scene van moved to make way for the medical examiners wagon to pull up to the building.
Police flanked both sides of the van all the way to the buildings entrance. After 10 somber minutes, a stretcher was wheeled out carrying a figure covered in black plastic and was loaded into the wagon before being quickly whisked away with blaring horns and blinding blue and red lights.
Earlier, neighbours said the actor looked ill when they last saw him.
"Just the other day I saw him getting out of his mini cooper with his kids and his wife I guess. He was in sweatpants and a beanie and he looked disheveled," said Olivia De Santis as more than 100 people gathered outside the actor's home.
The family of the actor issued a statement to the media in the aftermath of his death to thank everyone for their support.
"We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone. This is a tragic and sudden loss and we ask that you respect our privacy during this time of grieving.
"Please keep Phil in your thoughts and prayers."
In 2006, Mr Hoffman admitted his history of substance abuse after he graduated from NYU's drama school.
"It was all that drugs and alcohol, yeah. It was anything I could get my hands on ... I liked it all," he told 60 Minutes at the time.
Mr Hoffman, who was no matinee idol figure with his tubby build and scruffy blond hair, made his career mostly as a character actor. He was nominated for Oscars four times in all - best actor for Capote, which he won, and best supporting actor in The Master, Doubt, and Charlie Wilson's War.
In one of his earliest films, he played a spoiled prep school student in Scent of a Woman in 1992.
A breakthrough role came as a gay member of a porno film crew in Boogie Nights, one of several movies directed by Paul Thomas Anderson that he would eventually appear in.
He often played comic, slightly off-kilter roles in movies like Along Came Polly, The Big Lebowski and Almost Famous.
Just weeks ago, Showtime announced Mr Hoffman would star in Happyish, a new comedy series about a middle-aged man's pursuit of happiness.
In The Master, he was nominated for the 2013 Academy Award for best supporting actor for his role as the charismatic leader of a religious movement.
The film, partly inspired by the life of Scientology founder L Ron Hubbard, reunited the actor with Anderson.
He also received a 2009 supporting nomination for Doubt, in which he played a priest who comes under suspicion because of his relationship with a boy. Meanwhile, in Charlie Wilson's War he played a convincing CIA officer.
Mr Hoffman appeared in more than 50 films in a career that spanned less than 25 years.
Born in 1967, Mr Hoffman was interested in acting from an early age, mesmerized at 12 by a local production of Arthur Miller's All My Sons.
He studied theatre as a teenager with the New York State Summer School of the Arts and the Circle in the Square Theatre. He then majored in drama at New York University's Tisch School of the Arts.
Trained in the theatre, with a versatility and discipline more common among British performers than Americans, he was a character actor who could take on any role, large or small, loathsome or sympathetic.
On the stage, he performed in revivals of True West, Long Day's Journey Into Night and The Seagull, a summer production that also featured Meryl Streep and Kevin Kline.
In 2012, he was more than equal to one of the great roles in American theatre - Willy Loman in Death of a Salesman, a performance praised as 'heartbreaking' by Associated Press theater critic Mark Kennedy.
"Hoffman is only 44, but he nevertheless sags in his brokenness like a man closer to retirement age, lugging about his sample cases filled with his self-denial and disillusionment," Mr Kennedy wrote.
"His fraying connection to reality is pronounced in this production, with Hoffman quick to anger and a hard edge emerging from his babbling."
He also directed and acted in Off Broadway shows for the Labyrinth Theater Company, a New York troupe, which he served for a time as artistic director.
In 2003, he played James Tyrone, a doomed addict in Long Day's Journey Into Night.
"The theater was very difficult for him," the play's director Robert Fallstold the New York Times Sunday night.
"It cost him; there was an emotional cost to the work, having to do it for eight performances a week, and having to rehearse. In Long Day's Journey, a role about an addict who would be dead in a number of years, who was filled with self-loathing, certainly Phil had access to those emotions.
"But I'm not talking about a method actor. He just brought every fiber of his being to the stage. He was there - with his depth of feeling, depth of humanity - and no other actor I've ever worked with ever brought it like that, not at that level."
The actor was known for the enormous respect he commanded from his peers says director Shane Salerno who produced his documentary, Salinger, with the help of Mr Hoffman.
"To be honest, we were having trouble getting big names to participate," said Mr Salerno.
"But when he agreed to do it, other people began getting on board. Once Phil signed up, it was like we had a seal of authenticity," Salerno said to USA Today.
"The interviews he gave were as good as the Yale professors we spoke with. You can't imagine how intellectual he was about film, stage, literature. He was as smart as they come."
- The Daily Mail