Cameron Monaghan is the Joker in the TV series Gotham - a TV series which I will love to my dying day due to its awesomeness.

I don't really like calling people mad or crazy, but it's def. an intense role.

Heath Ledger did die after doing it, but I think his death was ruled an accidental overdose - his doctor had changed his prescription, and Ledger took the amount of tablets he'd need to take with the previous prescription. He had def. suffered from mental health problems, which was why he'd been prescribed sleeping pills in the first place.

Jim Carrey was an awesome Riddler though, I loved him in that role. Cory Michael Smith - who played the Riddler in Gotham (I can't help it - I love this series!) was amazing, and played the character in a v. different way.