Well-meaning drunk aerospace executive Tom Longman (Dean Stockwell) intervenes after seeing a wild-eyed creep (Thom Christopher) abusing a woman in the back of a bar. The creep identifies himself as Paul Rogan - a well-known violent psycho cult leader. Rogan leaves but finds Longman later and runs him off the road then he pulls a knife on Longman and chases him through an amusement park.
In a drunken stupor Longman stumbles and is knocked out. When he regains consciousness he is holding the now bloody knife and Rogan is dead from stab wounds from that very same knife. At his first moment of consciousness he is discovered by a security guard. Given Rogan's reputation not only can Longman walk on murder charges by claiming self-defence but the media will proclaim him a hero.
Longman will have none of it. He didn't kill Rogan. Longman's father (Morgan Woodward) hires fat, homely, short and balding private detective Frank Cannon (William Conrad) to troubleshoot. After Cannon fails to convince Tom Longman to claim self-defence he is left with plan b - finding out what really happened and proving it. That proves difficult when Rogan's 'family' i.e. brainwashed followers try to kill Longman and Cannon.
The Manson Family murders became fodder for fiction and movies and TV shows about crazed cults. For whatever reason the one depicted in this episode is a group of bored rich kids who like to play with guns. It seemed like Cannon was a show fixated upon the affluent and malevolent overlooking the fact that the vast majority of it's audience had little or nothing in common with characters like that.
As with any episode of this show the guest stars are the most impressive aspect of the production. Among them Thom Christopher and Randy Powell each excelled at playing baddies and cads in their careers in apparent avoidance of straight ahead roles. We see them here near the very beginning of their respective careers on the screen.
Laurie Walters ('Eight is Enough') appeared uncredited as a cult member.