United Kingdom, Oct. 14 -- Michael J. Fox's iconic Back to the Future guitar is missing.

The 64-year-old actor performed Chuck Berry's Johnny B. Goode on a red instrument in an iconic scene in the 1985 movie and while he "wishes" it was still in his possession, he has no idea what happened to the prop.

In an extract from his new memoir Future Boy: Back to the Future and My Journey Through the Space-Time Continuum shared by Us Weekly magazine, Michael wrote: "In the decades since the movie's release, the guitar used in Johnny B. Goode has grown more important for what it isn't than what it is. What it isn't is available.

"I wish I could claim to possess it, but I didn't have the foresight to know how valuable it would become.

"Somebody...