The 1968 Mustang GT used in Bullitt sold for $3.74 million at this weekend’s Mecum Kissimmee auction. That’s the most anyone has ever paid for a Mustang, according to the auction house.

The car, thought lost for many years, came back into the public eye early in 2018 . Although there were two Mustangs used for filming, this one was the Hero car—that is, the one used for slower shots that was treated well, as opposed to the stunt car, which was abused.

Although just how the world lost track of the car is a bit of a mystery, because by all accounts nobody was trying to hide it. In fact, the family who brought it back into the public eye owned it since 1974. Back in 2018, Sean Kiernan said that his mother used to drive it to work every day and that his dad bought it out of the classified section of a Road & Track.

Steve McQueen even tried to buy it back from the Kiernans at one point, but they wouldn’t let it go. They did nearly let it go to ruin, though. By the ‘80s the car wasn’t running and had garagitis.

Fortunately, the Kiernans got to fixing it back up and the car became a father son project. Sadly, Robert Kiernan, who bought the car in ’74, never got to see the car get back on the road. His son Sean, though, says that when he eventually summoned the courage to finish rebuilding the car, it was like therapy.

The car wasn’t fully restored, though, and still bears the patina of its years, just like McQueen always wanted.

Letter from Steve McQueen to Robert Kiernan​

Since its debut back into society, the Bullitt Mustang has gone on tour with Ford and even sat on the National Mall in Washington.

The car itself started life as a 1968 Mustang GT before being modified for the movie. It has a 390 V8 with a four-speed manual transmission. It was debadged for filming and also had its suspension beefed up to make sure it could handle jumping around the streets of San Francisco.