John Kenney's fatal feud with Carmel Valley neighbors airs tonight on Dateline

The hour-long episode features the fatal feud between former Carmel Valley neighbors John Franklin Kenny, then 72, and Mel and Elizabeth Grimes.

Kenney of Carmel Valley, was sentenced in November to life in prison without the possibility of parole. Two months prior, he was found guilty by jurors of first-degree murder in Elizabeth Grimes' death and second-degree murder in the death of her husband, Mel Grimes, outside their homes off Southbank Road in 2007.

The conviction included a gun enhancement tied to Kenney's use of a semi-automatic .45-caliber gun in the fatal shooting.

Kenney received life in prison without parole because he was convicted of multiple murders - one of them in the first degree.

The fatal confrontation between the neighbors culminated Jan. 29, 2007, soon after Kenney had placed a 1-ton boulder on a slice of disputed land dividing their properties. The killings ended a years-long quarrel that involved lawsuits and counter lawsuits and restraining orders from both neighbors.