Serial killer Charles Manson has been engaged to marry since last autumn, but it appears for now he will remain one of the most notorious bachelors in prison.
The 80-year-old mass murderer technically has until Thursday to tie the knot with Afton Elaine Burton, who is 54 years his junior.
But Burton will not be able to visit him in California State Prison until the weekend, meaning the deadline for their 90-day marriage licence will expire.
State corrections spokeswoman Terry Thornton said prison officials had no idea why Manson and Burton failed to exchange vows.
The couple will now have to obtain a new marriage licence to extend their engagement.
Burton, who goes by the name Star, reportedly moved to California to be near Manson nine years ago.
California state law allows inmates to marry in prison ceremonies but Manson would not be eligible for conjugal visits because he has been denied parole.
Manson gained notoriety as a cult leader in the 1960s which led to the murder of seven people, the most famous of which was Roman Polanski's wife Sharon Tate.
Tate was eight months pregnant with Polanski's son when she was killed on Manson's orders in 1969.
Since being jailed, Manson has been denied parole a dozen times since 1978, most recently in 2012.
He has not attended a parole hearing since 1997 and his next hearing is not scheduled until 2027.