Michael J. Fox himself has reflected on how strange the movie's core concept is, noting it's a film about "almost f***ing your mom". Critics often point out how the film somehow makes this "incestuous" complication funny rather than unsettling.

While critics often call it a "perfect blockbuster" with a "flawless script", some of the most interesting reviews of Back to the Future focus on the "bizarre" and "weird" nature of its central premise—particularly the subplot involving Marty McFly's mother.