AceShowbiz -

Joss Whedon returned to Twitter to take on Donald Trump with a star-studded super PAC. The filmmaker enlists "The Avengers" stars Robert Downey Jr., Scarlett Johansson, Mark Ruffalo, Cobie Smulders, Don Cheadle and Clark Gregg, in addition to many other famous faces like Nathan Fillion, James Franco, Neil Patrick Harris, Julianne Moore and Martin Sheen for the video promoting Save the Day.

In it, the actors hilariously yet seriously urge Americans to vote for Hillary Clinton without mentioning her name. "Do we want to give nuclear weapons to a man whose signature move is firing things?" Leslie Odom Jr. asks. Cheadle, meanwhile, indirectly refers to Trump as "a racist, abusive, coward who could permanently damage the fabric of out society."

"And if you do vote, and help protect this country from fear and ignorance, Mark will do a nude scene in his next movie," they promise, much to Ruffalo's surprise. "Make Mark be naked," Smulders adds.

To The Hollywood Reporter, Whedon explains why he made the PSA. "It's not about attacking because Donny's real good at attacking himself," he says. "It's about getting people to vote, because it's frightening the apathy that people are treating the most crucial election of their lifetimes with."

"Grey's Anatomy" actor Jesse Williams, Keegan-Michael Key, Stanley Tucci, "Blindspot" star Ashley Johnson are also featured in the video. Watch the behind-the-scenes video from the making of the PSA below.