Part I: Three patients in an Intensive Care Unit die after being injected with digoxin, a drug that had not been prescribed. Each had a faint tattoo on their arm reading 'Let Me Go',implying voluntary euthanasia was involved, though one of the tattoos actually read 'Let Me go Back.' The chief suspects are Dr Elizabeth Walker,an advocate of euthanasia and Carl Burgess,an obsessive ward orderly who behaves oddly. Part II: Burgess confesses to the murders but it is only to protect Dr Walker,whom he believes is the real killer,and on release commits suicide. Creegan is convinced that all the victims were brought to the brink of death and then resuscitated to tell the perpetrator what life on the other side is like. Using his own near death experience he flushes out the murderer who threatens to kill more patients if Creegan fails to satisfy. He must prevent this from happening.