Tom Selleck is famous for a lot of things -- Three Men and a Baby, his role on Friends, his timeless mustache -- but in general, he's known for playing two types of characters: cowboys and detectives. Ironically, he doesn't seem to have ever played a sheriff, but in the new fall TV series Blue Bloods, he plays an NYPD police chief with three children who are also in law enforcement. It seems like the natural fit for the gruff authority figure, who's also played King Ferdinand and President Eisenhower, but mostly, it's a great next step in his career of playing crime-fighters, whether government-sponsored or independently licensed. Here are some of his best cop and detective roles.

Tags: Blue Bloods, Magnum. P.I., Tom Selleck