Oscar winner Anne Hathaway teamed up with James Corden for one of the funniest rap battles in recent years.
"You're the worst British export since smallpox!" Anne rapped at one point.
The Les Miserables star, 33, is no stranger to picking up the mic live on TV - she has previously surprised in the US version of Lip Sync Battle.
But up against the host of The Late Late Show, Anne was clearly having a blast, despite the Gavin & Stacey star's cutting rhymes.
James rapped: "I'm gonna try my best and air it out like tank tops, and like her movie Get Smart, her rhymes are gonna flop!"
Anne went for the low blow - the ratings for James' show.
"I can't make fun of you James, cos no one's heard of you. Now that I finally have a chance to speak, I saw your rhymes are like your ratings, damn, they're incredibly weak."
"I'm like your wife," she rapped. "I watch Seth Meyers instead."
Ouch. That's gotta hurt.
As the insults continued, James made a reference to Anne's disastrous turn hosting the Oscars alongside James Franco in 2011.
"Trust me, I won't lose this to an impostor. It's more likely they'll ask you again to host the Oscars!"
Anne hit right back with: "Blimey guv'nor, did me accent make you sick? Are you also allergic to wearing suits that fit?"
James countered with a lyric suggesting Anne "should kiss his f*****g a**e." He also waved his bottom in her direction.
Anne took it up a notch with a message to her "Hathahaters" and James.
"I heard everything man, and none of it broke me. I battle with love and joy, so I am always unafraid. But son, now you know how it feels to get Hatha-slayed!"
The crowd gave it up for Anne with a rapturous reception and loud cheers. She was crowned the winner, but there were no real losers.