The two went head to head in BBC Radio 1's always hilarious "Playground Insult" segment, where costars have to hurl disparaging remarks at the other until someone either loses it or delivers a "killer insult."
ScarJo started with an outright lie right off the bat. "Chris, you're ugly. Everyone's been talking about it," she told him, "You're just really ugly."
His clapback game was strong though, saying, "Beauty is on the inside and inside you is just awful."
From there, the two exchanged barbs about their outfits -- with Johansson criticizing Chris' "grandma cardigans" and him taking aim at her pants -- before he dissed his costar's superhero alter ego.
"What's Black Widow's superpower again? Owning little tasers?" he asked.
"Chris spends more time in the hair and makeup chair than all of us," Johansson then revealed. "What are you doing in there? Getting a full face lift? I'm waiting on the set like everyone else, 'Where the hell is Chris Hemsworth?'"