10. Sebastian (Sheldon's Old Roommate) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?rf=homepage)

9. Dimitri (The Genius Janitor) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=2)

8. Joey (The Doorman) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=3)

7. Dr. Gallo (Leonard's Psychiatrist) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=4)

6. Dr. Elizabeth Plimpton (Dr. Slutbunny) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=5)

5. Dennis Kim (The Boy Genius) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=6)

4. David (The Sexy Nerd) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=7)

3. Mrs. Latham (The Donor Who Has The Hots For Leonard) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=8)

2. Angela Page (The FBI Agent) (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=9)

1. Gilda (https://whatculture.com/tv/the-big-bang-theory-10-characters-you-totally-forgot-existed?page=10)