A new documentary sheds light on the search for Marty McFly's red guitar from Back to the Future, which has been missing for 40 years.

Marty McFly's red guitar from the original "Back to the Future" is missing and the movie's cast and filmmakers are asking for the public's help.

The film made two crucial errors in its iconic dance scene, where Fox's McFly performs "Johnny B. Goode" on a now-famous Gibson ES-345