There is a major plot flaw with this episode: It is established early on in the episode that Starsky and Hutch went through 'the academy' with John Colby and they know him well. In fact, they both recognize him immediatly and call him by name. So it is a fact that his name is in fact John Colby. He tells our heroes of the horrors of his military experience, and then explains about his ex-wife and missing son. The boys try to help thier old buddy by finding his ex-wife and kid, not realizing he is really a hit-man looking for his (supposed) ex-wife to get to her husband, Warren Karpel, a material witness in a big court case, so he can assasinate him.
In several scenes, the ex-wife makes mention of her first husband, John Colby, who never came back from the 'war'. So this establishes that she did indeed have at one time a husband named John Colby who was in the 'war' but never returned, right?
When 'John Colby' finally meets up with Mrs. Karpel in the parking lot, she lets it be known that she has never seen this man before in her life! Which means that he really isn't 'John Colby', right?
So, what do we have here: Starsky and Hutch have an old friend that was 'lost' at war named John Colby. Mrs. Karpel has a past husband that was 'lost' in the SAME WAR named John Colby, but not the same John Colby that Starsky and Hutch know? If he really isn't John Colby,who is he? And why do our heroes know him as John Colby? It is all very confusing... [Editor note: Karen Karpel only refers to her first husband by his first name, 'John', without a last name. Since John's the most common first name in the English language it makes for a coincidence but not an unusual one. I've left the original trivia blurb here in case there's any future confusion.]