Roger Andermatt was born in 1969 in Lucerne, Switzerland. He worked as a nurse in various retirement homes across central Switzerland, including the Eichhof retirement home in Lucerne. Beyond his nursing career, Andermatt was known locally as a dance teacher and DJ under the name "R.O-Gee."

Between 1995 and 2001, Andermatt exploited his position as a nurse to murder patients under his care. His victims, primarily elderly individuals aged between 66 and 95, were in need of care and resided in nursing homes where Andermatt was employed. He confessed to killing 27 patients, although he was convicted for 22 murders. His methods included administering lethal doses of medication or smothering victims with plastic bags and towels.

The murders came to light due to an unusual accumulation of deaths in certain nursing homes. Authorities exhumed and autopsied the bodies in 2001, leading to Andermatt's arrest on June 28, 2001, following a suspicious death in a Lucerne nursing home. During interrogation, he admitted to the killings, claiming he acted out of compassion to end the suffering of his patients.

On January 28, 2005, the Lucerne Criminal Court sentenced Andermatt to life imprisonment for 22 counts of murder, three counts of attempted murder, and two counts of unfinished murder. The court's punishment exceeded the prosecutor's request and rejected the defense's argument of killings out of sympathy. In a subsequent hearing on February 15, 2006, the Lucerne High Court upheld the life sentence, convicting Andermatt of seven murders, with the remaining 15 cases classified as deliberate killings.