Jon Hamm, Questlove, Joel McHale Take On Sexual Assault in White House PSA

Stars join President Obama and Vice President Joe Biden in "It's on Us" video

Jon Hamm is serious about taking on sexual assault.

"It's on us to stop sexual assault," Hamm says, opening the White House's latest PSA on sexual assault, which shifts the responsibility to stop assaults from the victim to men and bystanders. He's joined by Questlove, Joel McHale and Kerry Washington to lend star power to the White House initiative.