I'm going to start by noting the several legendary characters actors in this episode of Ironside. I'm not talking academy award winners, I'm talking actors who did hundreds of TV shows and movies and became familiar faces to every sentient American from the 1950's through, well, now, due to DVD's and syndication.
You've got Richard Jaeckel, who was a mainstay in westerns, war films, and TV. He not only did the classics like Alfred Hitchcock Presents and Outer Limits, but was most memorable in the 1967 classic movie, The Dirty Dozen.
You've got Gene Lyons, our beloved Commissioner Dennis Randall, who is starting to look worse for the wear. He will die in a couple of years of alcoholism.
You've got - uncredited! - Ken Lynch. Lynch must have played a zillion policeman and hoods, from shows like Andy Griffith to Perry Mason to Twilight Zone to Alfred Hitchcock, he did them all, and with earnest class.
And then there's Ed Lauter. One look at his face and you'll say, I know that guy. Of course you do, he was omnipresent in show business as a character actor.
Finally, Jackie Cooper was often a lead, but he also did many character parts. He acted from 1929-1990, starting in the Little Rascals. Notably, he got to be a murderer in Columbo and Perry White in the Superman movies.
Salud to them all.
The actual plot is a classic - the idea of a bomb attached to something or traveling around and the heroes racing the clock before it blows. It was done in a Thriller episode and of course in the famous Sandra Bullock/Keanu Reeves movie, Speed.
Ironside does it very well and the ending is very, very clever as to how they get around it.
One odd thing: The episode was originally aired (and still on DVD's menus) as out of sequence in the Ironside universe. At the end Mark happily announces he's been accepted into the police academy. Well, at the beginning of season 6 he was already in the academy and in the episode preceding this he was done with the academy and back to being assigned to the Ironside crew as a regular policeman!
The Ironside/Star Trek connection: Lyons, of course, from original Star Trek, and Ken Lynch appeared in the classic Star Trek episode, "Devil in the Dark," where Spock mind melds with the Horta. "Paiiiiiiinnnnnn....paiiiinnnnnnn!"