Tarantula movie poster (on the far right) at the Pohatchee Drive-In.

Marty: "Clint Eastwood never wore anything like this."
Doc: "Clint who?"
Marty: "That's right. You've never heard of him."
— Marty after trying on new clothes with the poster behind him.

Tarantula was a film released in 1955. It was played at the Pohatchee Drive-In Theater. Unknown at the time, it featured one of the first appearances of Clint Eastwood. Ironically, Marty McFly would use his name as his alias in 1885.