Photographers' flashbulbs greeted the arrival in a packed court of a handcuffed Armin Meiwes, a computer repairman who had cut up and consumed a man he had met via the internet.
The bizarre case of sexual fetishism and gory details of the crime have transfixed the public, while legal experts have argued over the definition of murder.
Cannibalism in itself is not outlawed in Germany.
But if it can be proven that Meiwes, 44, killed to satisfy sexual desire or to commit another crime, in this case "disturbing the peace of the dead", he could face life in prison.
Meiwes was first sentenced in January 2004 to eight and a half years in prison for manslaughter, but the Supreme Court ruled last April that the judges had been too lenient and ordered a retrial.
In a dark suit, and thinner than at his first trial, 44-year-old Meiwes listened again to prosecutor Marcus Koehler's description of his crime.
Freed from the handcuffs, he sat back without obvious emotion, though he later exchanged smiles with his lawyers.
Victim wanted to be eaten
Meiwes has admitted killing Berlin-based computer specialist Bernd-Juergen Brandes but had been spared a murder conviction and a possible life sentence because the victim had wanted to be eaten.
The 43 year old met Meiwes after replying to an Internet advertisement for "young, well-built men aged 18 to 30
for slaughter".
He was one of more than 200 people who replied to the advertisement.
In March 2001, Mr Brandes, who had a will, bought a one-way rail ticket to Meiwes' hometown of Rotenburg, where his host picked him up at the station and took him to his rambling half-timbered farmhouse.
The two men had sex and after Brandes downed sleeping pills and whiskey, Meiwes cut off the man's penis, which they planned to eat together but found it was inedible.
"Due to the consistency of the penis, this did not succeed, either raw or fried," Prosecutor Koehler said.
When Mr Brandt fell unconscious, Meiwes slit his throat, pulled out his organs and chopped off his head.
He dissected the corpse, slicing off 30 kilograms of flesh which he stored in a freezer.
Meiwes later ate two-thirds of it, often with accompaniments such as pepper sauce or a wine sauce and potatoes.
"He (subsequently) watched the video of the killing of Brandt for his sexual pleasure," Prosecutor Koehler told the court.
The case did not come to light until an Austrian student spotted another Internet advertisement by Meiwes seeking new victims and alerted the police.
Germany's top criminal court said the first trial court had ignored the fact that Meiwes had filmed the slaying for later sexual gratification, a fact that could tip the scale in favour of a murder conviction.
His defence team countered that Meiwes had merely acceded to his victim's wishes and that his crime was only "killing on request", a form of illegal euthanasia that carries a maximum five-year sentence.
Lawyer Harald Ermel acknowledged his client had a "fetish for human flesh", but said he was no longer a threat.
"Under the same circumstances he would never do something like that again," he said.
Disturbed but sane
Psychiatrists found Meiwes deeply disturbed but sane and is criminally accountable for his actions.
Meiwes's lawyers pointed out that he had earlier released four other potential victims who changed their minds at the last minute and drove Mr Brandt back to the station in the town of Rotenburg after the victim initially appeared to lose his nerve.
Lawyer Joachim Bremer said Mr Brandt had made it quite clear through email, internet chat and telephone conversations about his wish to end his life.
"He made this clear to others and left no doubt about the seriousness of this desire," Mr Bremer said.
A verdict is expected in March.
Ahead of the trial, Meiwes filed requests with US and German courts for an injunction to block the release of a Hollywood film he claims is based on his case, saying the movie could prejudice his retrial.
Meiwes is reportedly working with a television production company on a documentary about his life.