A New York City man convicted of murdering a motivational speaker says the self-help expert was grimly determined to die.

Kenneth Minor spoke to CBS’ “48 Hours Mystery” in his first interview about Jeffrey Locker’s death. The piece airs Saturday.

Minor’s case broached the concept of assisted suicide in the unusual context of strangers staging a violent death.

Both Minor and Manhattan prosecutors say Locker approached him on a street in July 2009. They say Locker offered to pay to die in a seeming robbery so his family could collect life insurance money.

Minor says in the interview that Locker told him: “This is getting done.”

Prosecutors said Minor went beyond aiding suicide by stabbing Locker. He said he just held a knife while Locker lunged into it.