1. Snoop Dogg
He played: Himself — he recorded a song with Big Time Rush.
Where you know him from: He's a suuuuuper-famous rapper.
2. Jordin Sparks
She played: Herself — she fell down a well and then recorded a song with BTR.
Where you know her from: She's a Grammy-winning singer-songwriter who rose to fame when she won Season 6 of American Idol. Since then, she's had hits like "Tattoo," "No Air," and "Battlefield."
3. Camilla Luddington
She played: Rebecca — the assistant to Gustavo's archnemesis, Hawk. She tried to sabotage BTR from performing at a concert and tied them up.
Where you know her from: She's best known for playing Jo Wilson on Grey's Anatomy.
4. Alexa PenaVega
She played: Herself — she teamed up with BTR to stop a spy from ruining the Tween Choice Awards.
Where you know her from: She starred in Spy Kids, and she's Carlos PenaVega's wife IRL.
5. Fabio Lanzoni
He played: Himself — he was in a few episodes, and he tried to sell "Pocket Grillers," went on a date with Kendall's mom, and became BTR's neighbor.
Where you know him from: He's an actor, a model, and best known for his luscious, shiny hair.
6. Erik Estrada
He played: Officer Garcia, Carlos's dad — he helped Carlos find his missing helmet.
Where you know him from: He's an actor who's starred on shows and in movies like CHiPs, The Bold and the Beautiful, Two Women, One Road, Loaded Weapon 1, Van Wilder: Party Liaison, and Sealab 2021.
7. Nick Cannon
He played: Himself — he introduced BTR during the Tween Choice Awards.
Where you know him from: He started acting on Nickelodeon's All That, then went on to host shows like The Nick Cannon Show, America's Got Talent, and The Masked Singer. He is also a rapper and has released numerous tracks.
8. Lisa Rinna
She played: Brooke Diamond, James' mom — she tried to take James back to Minnesota so he could run her cosmetics company.
Where you know her from: She acted in Days of Our Lives and Melrose Place, then starred as herself in The Real Housewives of Beverly Hills.
9. Elizabeth Gillies
She played: Heather Fox — Carlos and James' old friend from camp who became a model.
Where you know her from: She's best known for playing Jade on Victorious and Fallon on Dynasty.
10. Jon Stewart
He played: Himself — BTR was supposed to appear on his show.
Where you know him from: He hosted The Daily Show from 1999 to 2015. He's also a bestselling author, director, and producer.
11. Keegan Allen
He played: A model.
Where you know him from: He's best known for playing Toby Cavanaugh on Pretty Little Liars.
12. Russell Brand
He played: Himself — Katie tried to become his manager, but he refused.
Where you know him from: He's a comedian and an actor best known for his appearances on Big Brother, Get Him to the Greek, Forgetting Sarah Marshall, and more.
13. Alfonso Ribeiro
He played: Block Captain McCallister.
Where you know him from: He played Carlton on The Fresh Prince of Bel-Air, Alfonso on Silver Spoons, and Dr. Maxwell Stanton on In the House. Currently, he hosts America's Funniest Home Videos.
14. Miranda Cosgrove
She played: Herself — she recorded a Christmas song with BTR.
Where you know her from: She's best known for starring on Nickelodeon's iCarly and Drake and Josh.
15. Cher Lloyd
She played: Herself — she recorded a song with James.
Where you know her from: She was on the seventh season of X Factor and released a bunch of music during the early 2010s. Her hits include "Want U Back," "With Ur Love," and "Swagger Jagger."
16. Lucas Cruikshank
He played: Himself — he was a guest at the hotel BTR lived in.
Where you know him from: He's best known for his YouTube character Fred Figglehorn.
17. Gavin DeGraw
He played: Himself — he was trying to produce a new song.
Where you know him from: He's a singer-songwriter best known for "I Don't Want to Be," along with many other hits, including "Not Over You," "Follow Through," and "Chariot."
18. Austin Mahone
He played: Himself — he was a guest and nominee at the Tween Choice Awards.
Where you know him from: He's a singer-songwriter who rose to fame after posting videos of himself singing on YouTube. His hits include "Say Somethin" and "Say You're Just a Friend."
19. Victoria Justice
She played: Herself — she was the opening act at BTR's concert.
Where you know her from: She's best known for her roles in Zoey 101 and Victorious.
