Bill & Ted's Excellent Adventure (1989)

After a high school lab experiment goes horribly wrong, Mordecai and Rigby must go back in time to battle an evil volleyball coach in order to save the universe — and their friendship.

Stillman, a heartbroken physics student, builds a time machine when his girlfriend breaks up with him. Going back in time, he attempts to save their relationship by fixing every mistake he made—while dragging his best friend along in the process.

What was a cunning plan from Lord Edmund Blackadder V to fake a time machine on his gullibly incompetent friends, turns out to be the real thing and hurls him and his imbecile underling, Baldrick, through the course of human history.

Young history buff Kevin can scarcely believe it when six dwarfs emerge from his closet one night. Former employees of the Supreme Being, they've purloined a map charting all of the holes in the fabric of time and are using it to steal treasures from different historical eras. Taking Kevin with them, they variously drop in on Napoleon, Robin Hood and King Agamemnon before the Supreme Being catches up with them.

Laura and Harrison have the picture-perfect romance built on the foundation of a shared love of music. After a deadly accident, Laura gets the chance to save the love of her life when she discovers that their mixtape can transport her back in time.

Marty and Doc are at it again as the time-traveling duo head to 2015 to nip some McFly family woes in the bud. But things go awry thanks to bully Biff Tannen and a pesky sports almanac. In a last-ditch attempt to set things straight, Marty finds himself bound for 1955 and face to face with his teenage parents -- again.

Lenny has relocated his family back to the small town where he and his friends grew up. This time around, the grown ups are the ones learning lessons from their kids on a day notoriously full of surprises—the last day of school.

On another planet in the distant past, a Gelfling embarks on a quest to find the missing shard of a magical crystal and restore order to his world, before the grotesque race of Skeksis find and use the crystal for evil.

Agents J and K are back...in time. J has seen some inexplicable things in his 15 years with the Men in Black, but nothing, not even aliens, perplexes him as much as his wry, reticent partner. But when K's life and the fate of the planet are put at stake, Agent J will have to travel back in time to put things right. J discovers that there are secrets to the universe that K never told him - secrets that will reveal themselves as he teams up with the young Agent K to save his partner, the agency, and the future of humankind.

A timid, nearsighted chemistry teacher discovers a magical potion that can transform him into a suave and handsome Romeo. The Jekyll and Hyde game works well enough until the concoction starts to wear off at the most embarrassing times.