17 Inspired and Surprising TV Crossovers

What do you get when characters from two or more shows team up? A crossover! Most recently, Supernatural's Sam and Dean got animated and met a certain mystery-solving pup on "ScoobyNatural."

That's not the only cool mash-up of TV series, though.

Let's hop into the Mystery Machine and take a trip through TV history to revisit some of the most memorable small-screen crossovers.

1. "ScoobyNatural" (Scooby Doo and Supernatural)

It took 13 seasons, but the Winchester Brothers are finally teaming up with the original Scooby gang in the TV crossover event of the year.

2. "The Stolen Earth" (Doctor Who, Torchwood, and The Sarah Jane Adventures)

The Tenth Doctor calls upon old friends to help save the Earth from the Daleks, including Captain Jack Harkness, Rose Tyler, Martha Jones and Sarah Jane Smith.

3. "How to Get Away with Scandal" (Scandal and How to Get Away with Murder)

Actually titled “Allow Me to Reintroduce Myself” and “Lahey v. Commonwealth of Pennsylvania,” this two-hour Shondaland crossover event brought two of TV's fiercest ladies together -- Olivia Pope and Annalise Keating.

4. "Hiding Not Seeking" and "Profiles" (Chicago Fire and Chicago P.D.)

This two-hour crossover event brings Intelligence together with Firehouse 51 to track down a bomber. It also celebrates P.D.'s 100th episode.

5. "I Will Remember You" (Angel and Buffy)

In a heartbreaking episode, Angel kills a demon that makes him human again, leading to a night of passion with Buffy. When he learns that Buffy's life is in peril, Angel begs the Oracles to make him a vampire again. Following a tearful goodbye, only Angel remembers the pure happiness that he briefly had with Buffy.

6. The Jetsons Meet the Flintstones

When a time travel experiment goes wrong, the Modern Stone Age Family meets the Family of the Future in a made for TV movie.

7. "The Seminar" (The Office U.S. and U.K.)

Also known as the episode where Michael Scott meets David Brent, fans of both the U.K. and U.S. series cheered when these two goofballs bump into each other on an elevator.

8. "Will is From Mars" (The Fresh Prince of Bel-Air and The Jeffersons)

Will and Lisa meet George and Weezy Jefferson at couples' counselling and hilarity ensues. Plus, it's not the last we see of the Jeffersons in Bel-Air. In the series finale, they buy the Banks residence.

9. "Crisis on Earth X" (DC TV)

A four hour event between Supergirl, The Flash, Arrow, and Legends of Tomorrow, this ambitious crossover had plenty of action, an alternate universe with evil doppelgängers, and even a wedding.

10. "The Resurrection in the Remains" and "Dead Men Tell No Tales" (Bones and Sleepy Hollow)

What sounded like an outrageous premise ended up being a fun Halloween crossover. Brennan is visited by the FBI's newest agent, Abby Mills, and her trusty man-out-of-time sidekick, Ichabod Crane. There's a mystery to solve, and it's going to take science and magic to find the answers.

11. "Fugue and Riffs" (Archer and Bob's Burgers)

In the Season 4 premiere, super spy Sterling Archer is suffering from amnesia and living as Bob Belcher -- husband, dad, and burger joint owner. What makes this one of the best crossovers is the fact that H. Jon Benjamin voices both Sterling Archer and Bob Belcher.

12. "Somewhere Over The Rerun" (Alf and Gilligan's Island)

Alf becomes obsessed with Gilligan's Island. He falls asleep when he should be helping Willie clean up a huge mess, and dreams that he's on the island with Gilligan, the Skipper, the Professor and Mary Ann.

13. "X-Cops" (X-Files and Cops)

In a monster of the week story, Mulder and Scully are interviewed by the reality TV show during an investigation. Mulder embraces the publicity while Scully doesn't think their work should be on national TV. Like Cops, the episode is shot on videotape and unfolds in real time.

14. “The Night Shift” and "Homecoming" (Brooklyn 99 and New Girl)

Jess Day and her friends head to NYC for an event at Schmidt's old high school. Hijinks ensue when Jess crosses paths with the 9-9's Jake Peralta.

15. "The One with Two Parts: Part 1" (Friends and Mad About You)

Mad About You's Jamie and Fran stop by Central Perk and mistake Phoebe for her twin, Ursula, the flaky waitress at Riff's.

16. "Something Good Coming: Parts 1 and 2" (Community and Cougar Town)

In Season 2 of Community, Abed tells Jeff that he was on an episode of Cougar Town and soiled himself. More cameo than crossover, Cougar Town incorporated Abed into a scene, and even had him running away post-accident.