After leaving M*A*S*H, Wayne Rogers took a chance on headlining a period piece crime drama that would re-establish him as a dramatic actor.
City of Angels came from the pens of Stephen J. Cannell and Roy Huggins, the latter of whom using a 1946 novel of his as part of his basis, just as he had done 20 years earlier with 77 Sunset Strip. However, Rogers, Cannell, Huggins, and NBC were working against recent television history. Quinn Martin had struck out twice in the previous three years with similar series, Banyon (for NBC, Martin's 1st sale to the network) and The Manhunter (CBS), that were, like Angels, set too far back in time for viewers' interests. What wasn't helping matters was that the definitive period crime drama, The Untouchables, which had Martin as an executive producer for its first three seasons, was in syndication at the time, and was the measuring stick by which viewers in the mid-70's were looking at these kind of shows. As a result, Angels, like Banyon and Manhunter, ended up cancelled after 1 season.
Rogers would later strike gold with another sitcom, House Calls.
The Rap Sheet serves up the intro, with narration by Rogers, in character as detective Jake Axminster.
Based on the description, it looked like Huggins was trying to create another Rockford Files, since there were some of the same tropes, such as Axminster, like Jim Rockford, often getting arrested on trumped up charges, but unlike Rockford, Axminster didn't have any friends on the police force.