Siobhan Thompson (born 29 July 1984) is a British-American sketch comedian and comedy writer. She is known for her work on the CollegeHumor Originals web series and has appeared in other programs such as Adam Ruins Everything and Broad City. She was also a staff writer for Adult Swim's Rick and Morty.

Filmography

• 2026Dimension 20 Live: Viva Más Vegas — Riva
• 2026Muppet Treasure Scriptland — Jim Hawkins
• Toonout — Vanellope Chapman (voice)
• 2026Wealwell's Guide to Reposed Standing — Vanellope Chapman (voice)
• Ask Hank Anything
• 2025Dimension 20 Live: Battle at the Bowl — Adaine Abernant
• 2025Dimension 20 Live: Gauntlet at the Garden — Misty Moore
• 2025Dimension 20 Live: Quangle Quest — Adaine Abernant / Ruby Rocks / Rosamund du Prix / Riva / Iga Lisowski
• 2025The Scripted Muppet Caper — Lady Holiday
• Dimension 20 Live
• Dimension 20: Time Quangle — Rowan Berry, Adaine Abernant, Princess Rosamund du Prix, Ruby Rocks
• 2024The Disruptors — Melissa
• Krapopolis — Writer, Executive Story Editor
• Mulligan — Story Editor
• Dimension 20 Animated — Ruby Rocks (voice), Princess Rosamund du Prix (voice), Adaine Abernant (voice), Riva (voice)
• Game Changer — Self - Contestant, Self (archive footage), The Voicemail Musical
• Troopers: Rise of the Budget — TR-45HY "Trashy" (voice)
• WTF 101 — Mary Toft (voice), Amsterdam Woman (voice)
• Breaking News: No Laugh Newsroom — O.K. Simpson, Jessica Crispy
• Dimension 20 — Adaine Abernant, Ruby Rocks, Imelda Pulse, Riva, Jaysohn, Princess Rosamund du Prix, Misty Moore / Rowan Berry, Iga Lisowski / Rowan Berry, Vanellope Chapman, La Contesse Madeleine d'Artois, Constance
• Bad Internet — The Hermione, Writer
• CollegeHumor Does the Purge — Siobhan, Writer
• CollegeHumor Goes to Hell — Siobhan, Writer
• Broad City — Leigh
• Rick and Morty — Writer, Staff Writer
• Arrested Development — British Reporter
• The Greatest Treasure in the World — Writer

Appearances as themselves (14)

• 2025Katie & Erika Throw the Perfect Father’s Day Party — Self
• 2025The Roll of a Lifetime: How Dimension 20 Sold Out Madison Square Garden — Self - Cast Member
• Gastronauts — Self - Judge
• Smartypants — Self - Society Member, Self - Presenter
• Thousandaires — Self - Host
• 2023The Legendary Rick Perry and the Art of Dimension 20 — Self (archive footage)
• Dirty Laundry — Self - Guest
• Dimension 20's Adventuring Party — Self
• Fantasy High: Extra Credit — Self
• The Rank Room — Self
• Total Forgiveness — Self
• Adventuring Academy — Self
• Um, Actually... — Self - Contestant
• Um, Actually: The Web Series — Self - Contestant