Katy Perry dropped a bomb to Billboard when she revealed she was plagued by suicidal thoughts after her breakup with Russell Brand. Now she's opened up to ET's Rob Marciano about how she overcame her darkest days.
"He literally is a genius, as is evident from his songwriting," she gushed to Billboard last month. "I always tell him, 'Darling, you know I'm going to have to give your mind to science after you've passed, because we're going to have to understand how all these sparks work.'"
To catch Perry's performance of her new song By the Grace of God, go to iTunes to stream her show from the iTunes Festival.