Serial killer Harold Shipman timed his suicide so his wife could cash in a £100,000 pension payout, according to secret prison records.
Shipman, who killed himself in his cell on the eve of his 58th birthday in 2004, planned his death so his wife Primrose - who continued to visit him every week after his conviction in 2000 - could receive the maximum pension payout.
Prison records obtained by the Sun on Sunday show he plotted to end his life before his 60th birthday so he could guarantee Mrs Shipman a £100,000 lump sum payment and £10,000 a year later from his GP pension.
If he died after that point she would have only been entitled to £5000 a year.
As well as suicide he was also considering goading another prisoner with a life sentence to kill him.
The files were supposed to remain secret until 2069 but a copy was found in the public records office at the National Archive in Kew, west London.
One document said: “Mr Shipman has stated he plans to kill himself in five years as this is the amount of time it takes for his pension to be secured for his wife.
“He has further commented that he will incite a lifer to attack him at this point with a view to being killed.
“Since his conviction it is indicated that Mr Shipman has received medication for (blank) and voiced suicidal thoughts prior to sentence.
“Following sentence it is reported that Mr Shipman again voiced suicidal intentions, stating that after he secured his pension for his wife he would end his life.
“It is indicated that his wife was in agreement that it was preferable to spending the rest of his life in prison.”
Shipman was convicted of murdering 15 of his elderly patients in Hyde, Greater Manchester but an inquiry later concluded he probably murdered 250 people over the course of his career as a GP.
One victim, a former mayoress, was given a fatal injection of diamorphine during a house call in 1998.
He later faked her will to make himself the sole beneficiary of her £386,000 estate.
In prison he was known to offer medical advice and was seen befriending an elderly, sick fellow inmate who claimed he had won the lottery.
On another occasion, he verbally threatened another inmate who would not stop talking saying he was a doctor and “knew where to cut [him]”.
He also reportedly told staff on a hospital wing: “I’m used to being in charge. I was high up the ladder as a doctor.”