The original cast of “Back to the Future” has reunited – not for a reboot, but to help locate a piece of movie history that went missing about 40 years ago.

For four decades, a crucial piece of cinematic history has been missing. It’s the iconic cherry red Gibson ES-345 that Marty McFly shredded during the legendary Enchantment Under the Sea dance scene in Back to the Future—an electrifying moment that sparked a generation of guitarists and cemented the instrument’s place in pop culture.

Four decades after the blockbuster film debuted, the guitar’s creator has launched a search for the iconic Cherry Red Gibson ES-345, asking for the public’s help tracking it down.