This entry in the Perry Mason series marked the first time that William R. Moses makes an appearance. He's young law school student Ken Malansky and they meet as Perry is giving a lecture to the participants of a moot court of soon to be graduates.
One of my favorite ironic moments in the Perry Mason series occurs in this film, Perry Mason: The Case of the Lethal Lesson. Raymond Burr gives a very good speech to the group about juries, people bringing all kinds of baggage from their every days lives to a jury. They're no better or worse than any other average group of folks you can get out of a phone book. But that as a jury they become a noble body and one should never demean them in any way.
It was a great moment of eloquence for Raymond Burr, one of the best in his career as an actor. It ought to be mandatory in law schools in fact. Yet we are talking about Perry Mason who never let a case get that far to a jury, at least not in any of the movies or the couple of hundred episodes from the original series that I recall.
Anyway among the participants of the moot court is John Allen Nelson, the spoiled son of Brian Keith who is an old friend of Burr's. He's a really rotten kid who's dad has used money and influence to get him out of trouble before. During moot court Moses threatens him and later goes out looking to him some bodily harm. But someone beat him to it when he finds the body and he's discovered with the corpse of the late Mr. Nelson. Of course Moses turns to Perry Mason for help.
For fans of the old television series, the character of Ken Malansky actually does have a precedent. For a couple of seasons Perry Mason had an actor named Karl Held play young lawyer David Gideon whom he also defended in a murder trial. Held popped up in a dozen or so episodes after that.
Anyway you know this kid had a host of people who didn't like him in his study group and others. But Perry ferrets out the killer in his usual manner.
William R. Moses joined the TV film series after that as William Katt as Paul Drake, Jr. departed for a series Top of the Hill that didn't last. Neither Moses or Katt have ever lacked for work however though they both are now forty somethings.
It's a good episode and fans of Billy Moses consider it a landmark.