The trial on a former male nurse accuse of killing 100 patients begins in Germany on Tuesday.
Niels Hoegel is accused of carrying out the murders between February 2000 and June 2005 in hospitals in the Lower Saxon cities of Oldenburg and Delmenhorst.
He is accused of randomly selecting patients – the oldest was 96 and the youngest 34 – and then injecting them with medication that led to heart failure or other complications so that he could try to resuscitate them.
The prosecutor claims he did this out of boredom or to impress his colleagues with his medical skills.
Hoegel was caught red-handed by a female nurse in the summer of 2005, but the extent of his crimes were not yet known.
No fewer than 130 bodies have since been exhumed for tests, including two in Turkey.
Police looked at 200 suspicious cases, but many patients who died at the two hospitals where Hoegel worked were cremated and could therefore offer no evidence.
Hoegel is already serving a life sentence for six other crimes.
The regional court in Oldenburg cannot accommodate the trial due to public interest so it is being held in a nearby Weser Ems festival hall.
There are 120 plaintiffs in the case, with many journalists and members of the public also expected to attend.
“[The plaintiffs] want to look the defendant in the eye,” lawyer Gaby Luebben said on Tuesday.