Secret letters infamous murderer Betty Broderick sent to her boyfriend begging for money and affection from behind bars have been published after being discovered in a forgotten San Diego storage unit.

Betty, 73, became a household name when she shot dead her ex-husband Daniel T Broderick III and his second wife Linda, the woman he had left her for, in November 1989.

The shocking double homicide captivated the nation and was even turned into a Netflix series this year with Christian Slater starring as Daniel and Amanda Peet appearing as the jilted ex-wife turned killer Betty in Dirty John: The Betty Broderick Story.

But Betty's boyfriend Bradley Wright, who she began dating before committing murder and who discovered the bodies of her victims, was not included in the television retelling of her crime.

The letters from 2003 to 2006 shed a light on Betty's time in prison and her relationship with Bradley who stayed in touch with his murderous girlfriend and sent her money well after her sentencing in 1991.