What happens when the world's greatest superheroes are forced to fight one another? That's what Captain America: Civil War will explore when it hits theaters in May 2016.

In the latest Marvel installment, Steve Rogers, aka Captain America (Chris Evans), risks everything to protect his pal Bucky (Sebastian Stan), who is wanted after he was brainwashed to fight the good guys in Captain America: Winter Soldier.

But Steve is determined to save his friend, even when some other Avengers — Black Widow (Scarlett Johansson) and Iron Man (Robert Downey Jr.) — are brought in to take Buck down.

"Sometimes I want to punch you in your perfect teeth," the quippy Tony Stark tells Steve.

But the jokes are pushed aside when they are forced to fight.

"You know I wouldn't do this if I didn't have a choice, but he's my friend," Steve says.

"So was I," Tony replies from inside his Iron Man suit.

Watch the trailer and tell Us what you think now!

Captain America: Civil War hits theaters on May 6.

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