In a twisted tale of love and passion, Hayley Palmer, a street robber has started making plans to marry a convicted serial killer, Joanna Dennehy.

The duo met and fell in love behind bars.

While Palmer has completed her sentence of 16 years in prison, her fiancee is serving life.

Daily Mirror reported that Palmer had taken legal advice on marrying the 38-year-old serial killer.

The killer, on her part, proposed to Palmer after they met at the privately-run HMP Bronzefield women’s prison, and is allowed no visiting rights.

Dennehy is one of only two female prisoners serving a whole life sentence in the UK, the other being House of Horrors killer, Rose West.

Dennehy was said to have stabbed three men to death over a 10-day period in March of 2013, before knifing two others, both of whom survived.

Branded “pure evil” by criminology experts, Dennehy of Peterborough admitted committing the murders because it was ‘moreish and fun.’

Her victims’ bodies were said to have be found in ditches in Cambridgeshire.

An unnamed source disclosed that “the only reason Joanna hasn’t killed anyone in prison so far is because Hayley wouldn’t let her.”

They have an agreement that Joanna shouldn’t attack anybody while she is in a relationship with Hayley.

“She hasn’t got in trouble in prison while dating Hayley and Hayley is more stable than ever.

“Hayley is looking to get human rights people involved as Joanna isn’t allowed visitation.

“Joanna is the more girly one so Hayley would not wear a dress for the wedding, she’d probably wear a suit.”

It was reported that Dennehy had wanted to kill nine men in total, to be like killers, Bonnie and Clyde.

She was caught two days after going on the run when police launched a triple murder probe.