Raiders of the Lost Ark - Starring Tom Selleck!

Most people already know this, but Tom Selleck was originally cast as Indiana Jones! His contract on Magnum P.I. prevented him from taking the role, which then went to Harrison Ford. It's hard to imagine anyone else in the role, although Magnum P.I. did do an episode that homaged Raiders and featured Selleck in a very Indy-esque get-up.

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