A 19-year-old Jack McAllister died from loss of blood after suffering 14 stab wounds, including one which severed a major artery, the Invercargill High Court was told on Thursday.
Christopher Brown (20), Laura Scheepers (19), Natasha Ruffell (27), David Wilson (20), and a 24-year-old woman with name suppression, are standing trial at the High Court, Invercargill, all facing a single charge of murdering McAllister.
Crown lawyer Riki Donnelly, in the opening address to the jury, said while none of the five defendants was physically involved in the stabbing, each had played their part.
Brayden Whiting-Roff, who has previously pleaded guilty to McAllister's murder, was the principal offender, Donnelly said.
McAllister, also known as Jade Fearn, died from injuries sustained during an attack at Stadium Southland on June 7 last year.
The crown alleged McAllister had been lured to Stadium Southland by Laura Scheepers, with the promise of sex, to lull him into a false sense of security, who then relayed where she was to defendant Christopher Brown.
The other defendants, along with Whiting-Roff, arrived at Stadium Southland, where the assault took place, Donnelly said.
He said there was "significant animosity" towards McAllister by a number of individuals in the group, based on a belief McAllister had acted "inappropriately" towards girls.
Donnelly said evidence would show the defendants had a shared understanding of the elements involved leading up to the incident, and each knew the probable consequences of their assistance.
Members of the jury were shown CCTV footage of the incident at Stadium Southland, including a moment the crown alleges was Whiting-Roff stabbing McAllister.
Because of the number of defendants and security required, family members and the general public will view the trial from a separate court room.
Justice Rachel Dunningham told the court the jury empanelling was the longest she had seen by far.
Forty-six potential jurors were excused, and another 19 were challenged by the defence or crown before the jury of seven women and five men were selected.
The trial is expected to run for five weeks.