The 1968 Mustang Bullitt GT featured alongside Steve McQueen in the film "Bullitt" sold for $3.7 million to a bidder whose identity is only known by one person, USA TODAY reported.

"Only one person knows the buyer, and that's the guy he was on the phone with," explained Sean Kiernan, who auctioned off the highland green Mustang on Friday in Kissimmee, Florida. "Eventually, it'll come out. But right now, no one knows." FOX BUSINESS