Mark O'Sullivan is a producer, actor, and writer known for Tell Me Everything (2022), Lee and Dean (2017) and My Sexual Abuse: The Sitcom (The Actual Sitcom) (2024). Mark won an RTS award in 2025 for his documentary (and sitcom episode) My Sexual Abuse: The Sitcom, made by Swan Films for Channel 4, was awarded the best Arts programme for 2025.