George Peppard starred as Thomas Banacek, a private insurance investigator of Polish descent based in Boston who became involved in various insurance fraud cases involving art, books, coins, horses, etc. He demanded and received a big fee for his services, which made him a very wealthy man, and enabled him to live well indeed, and he was quite the natural ladies man, in just about every episode! He was helped by his sidekick/chauffeur Jay Drury, played by Ralph Manza, whose theories about the cases were always wrong, and also Murray Matheson as Felix Mulholland, a book seller who provided Banacek with vital information he needed to solve his cases, all of which were very entertaining.
This had a memorably breezy theme, and was great fun to watch. Sadly, this only lasted two years and 17 episodes, because Peppard quit for personal reasons, which was a great pity, since this show could have gone on as long as "Columbo" did.