Selleck first TV appearance was as a college senior on The Dating Game in 1965 and again in 1967 - he lost both times. Soon after, he appeared in commercials for products such as Pepsi-Cola. He began his career with bit parts in smaller movies, including the over-the-top Myra Breckinridge and Russ Meyer's The Seven Minutes. He also appeared in a number of TV series, mini-series and TV movies.

Selleck, after years of little interest, was cast as Magnum, P.I. and Indiana Jones in Raiders of the Lost Ark in the same year. Magnum, P.I. producers would not release the actor and he had to pass on the film role, which then went to Harrison Ford.

He starred in the 1979 TV movie Concrete Cowboy with Jerry Reed. Selleck starred in a number of film roles during and after Magnum; among the most notable were as an acrophobic police detective in Runaway, as a stand-in father in Three Men and a Baby, and as an American cowboy in the Australian western Quigley Down Under, a role and film that he considers one of his best. His other films include Three Men and a Little Lady, High Road to China, Lassiter, Her Alibi, An Innocent Man, Folks!, Christopher Columbus: The Discovery, Mr. Baseball, In & Out and The Love Letter.

Selleck has also appeared in a number of made-for-TV movies in recent years. In particular, he has sought to help bring back to popularity the western, often playing one of that genre's typical characters but thrust into a modern context.

Most recently, Selleck has appeared in a recurring role on the acclaimed ABC drama Boston Legal as Ivan Tiggs, the troubled ex-husband of Shirley Schmidt (Candice Bergen), and as novelist Robert B. Parker's character Jesse Stone in several CBS made-for-TV movies, earning a 2007 Emmy nomination for Jesse Stone: Sea Change. (wikipedia.org)