Celebrity Name Guessing Game Can You Guess These Stars' Birth Names?

7/18/2015 12:01 AM PDT

One of Hollywood's worst kept secrets? Almost everyone goes by a stage name.

Don't believe us? Check out these 20 stars who adopted a fake name -- and see if you can determine what's printed on their birth certificates! 

20. Bruno Mars

19. Ben Kingsley

18. Carmen Electra

17. Demi Moore

16. Elton John

15. Gene Simmons

14. George Michael

13. Helen Mirren

12. Lana Del Rey

11. Larry King