• The Crown has changed its version of events since the 2002 trial. It is now alleged Lundy killed his wife and daughter in the early hours of August 30.
• The Crown says the murder was made to look like a "random burglary" but bloody marks on the outside of a window prove that was not the motive.
• DNA traces on a polo shirt Lundy wore on August 29 look set to be a key piece of evidence. The Crown says they contain Christine Lundy's brain matter but the defence disputes that.
• The Crown will call a former cellmate of Lundy's to whom he allegedly made "a jailhouse confession" but the defence will attempt to discredit him and called him "a liar" in its opening.
• The defence says that despite having "a sporadic sexual relationship" the Lundys were very happy and not under financial pressure after a recent investment in a vineyard.
The Crown now believes Mark Lundy killed his wife and daughter about six hours later than its original estimation.
The retrial in the High Court at Wellington began this morning at which Crown prosecutor Philip Morgan, QC, revealed the new version of events he said resulted in a "ferocious" double murder.
At Lundy's original trial in 2002, the alleged facts involved Lundy committing the brutal acts about 7pm on August 29 after a high-speed drive from Wellington to Palmerston North, before returning to a Petone motel at similarly breakneck speed.
Mr Morgan said that was no longer the Crown case.
He said Lundy, who ran a small kitchen business with his wife Christine, went to Wellington on one of his typical selling trips.
It is alleged he hired a prostitute before driving home in the early hours of August 30 and bludgeoned his family to death using a "sharp, heavy implement" thought to be a tomahawk or small axe.
"You may think the ferocity of the attack and the whereabouts - particularly on Christine Lundy - was carried out by someone who had hostility, to put it mildly, towards her," Mr Morgan said.
Lundy's 7-year-old daughter Amber was found in the doorway to her parents' room while her mother was found in bed later that day after a routine visit by her brother.
Mr Morgan said the incident had been made to look like "a random burglary" but the fact Mrs Lundy's blood was on the outside of the window, which had been jimmied open, showed it must have been done after the killing.
Much of the Crown case is expected to hinge on DNA evidence.
Police found a polo shirt turned inside out - which Lundy said he had worn the previous day - in Lundy's car when they stopped him on his way into Palmerston North on August 30.
When tested, scientists found two tiny samples of tissue which they believed to be from Mrs Lundy's central nervous system.
"Put simply, the accused had Christine Lundy's brain on his shirt when he returned to Palmerston North from Wellington," Mr Morgan said.
He conceded there was no CCTV footage or eyewitness who saw the murder but said the evidence "collectively" placed culpability squarely with Lundy.
In the defence's opening, Ross Burns was quick to quash the Crown's theories and said the fact their version of events had changed since the first trial proved his client had been wrongly convicted.
The Crown will call a former cellmate of Lundy's.
The inmate allegedly told Lundy why he was in prison and it is alleged Lundy told the cellmate "he wouldn't be there if it wasn't for his daughter coming in and seeing what he was doing to his wife".
However, Mr Burns called the man a "liar" and said he had a string of dishonesty convictions.
He also rejected the prosecution's assertion that the Lundys' "sporadic sexual relationship" was a symptom of an unhappy marriage and said all those who knew them believed the couple were content.
"Police suffered from tunnel vision from a very early stage," Mr Burns said.
The Crown painted a picture of extreme financial turmoil because the Lundys had recently invested in a vineyard but defence counsel said the defendant had not been under pressure.
Mr Burns said Lundy was described by those close to him as "loving and affectionate" to his wife and had "adored" his daughter.
Tomorrow the jury will hear from Mrs Lundy's brother who was the first to find the pair dead, as well as others who spoke to the victims before their death.
Lundy was remanded on bail to a "local address".
The trial before Justice Simon France is expected to last up to nine weeks.