'Avengers: Age Of Ultron' Clip: Science Bros Fist Bump

Our Marvel heroes will have plenty of baddies to fight in Avengers: Age of Ultron, but one of the biggest showdowns teased in the promo is the one between two Avengers: Iron Man (Robert Downey Jr.) and the Hulk (Mark Ruffalo). And what a showdown it is. Even in his specially made Hulkbuster armor, Iron Man struggles to hold his own against the unfriendly green giant.

A new action-packed clip delves into that battle, and even has a line explaining why the Science Bros are fighting in the first place. Here's a hint: It's exactly what you think it is. Watch the Avengers Age of Ultron clip after the jump. 

The Avengers Age of Ultron clip debuted at this weekend's MTV Movie Awards.

Just as everyone suspected, Scarlet Witch's (Elizabeth Olsen) mind-bending powers are what's turning these two heroes against each other. In the clip, Tony attempts to reason with Bruce: "That girl is just messing with your mind. You're better than her, your stronger than her. You're Bruce Banner."

Unfortunately for him, the Hulk is the one who hears the message, and he doesn't have much use for reason. He rampages through the city, pausing only when Iron Man gets in his way. The weirdest part of this scene is all the people scrambling to get out of the way. You'd think they'd have hightailed it out of there the moment these two behemoths started going at it, rather than waiting around until their fruit stands got reduced to Popsicle sticks.

Avengers: Age of Ultron lands in theaters May 1.

Marvel Studios presents "Avengers: Age of Ultron," the epic follow-up to the biggest Super Hero movie of all time. When Tony Stark tries to jumpstart a dormant peacekeeping program, things go awry and Earth's Mightiest Heroes, including Iron Man, Captain America, Thor, The Incredible Hulk, Black Widow and Hawkeye, are put to the ultimate test as the fate of the planet hangs in the balance. As the villainous Ultron emerges, it is up to The Avengers to stop him from enacting his terrible plans, and soon uneasy alliances and unexpected action pave the way for an epic and unique global adventure.

Marvel's "Avengers: Age of Ultron" stars Robert Downey Jr., who returns as Iron Man, along with Chris Hemsworth as Thor, Mark Ruffalo as Hulk and Chris Evans as Captain America. Together with Scarlett Johansson as Black Widow and Jeremy Renner as Hawkeye, and with the additional support of Don Cheadle as James Rhodes/War Machine, Cobie Smulders as Agent Maria Hill, Stellan Skarsgård as Erik Selvig and Samuel L. Jackson as Nick Fury, the team must reassemble to defeat James Spader as Ultron, a terrifying technological villain hell-bent on human extinction. Along the way, they confront two mysterious and powerful newcomers, Pietro Maximoff, played by Aaron Taylor-Johnson, and Wanda Maximoff, played by Elizabeth Olsen and meet an old friend in a new form when Paul Bettany becomes Vision. Written and directed by Joss Whedon and produced by Kevin Feige, p.g.a., Marvel's "Avengers: Age of Ultron" is based on the ever-popular Marvel comic book series "The Avengers," first published in 1963. Louis D'Esposito, Alan Fine, Victoria Alonso, Jeremy Latcham, Patricia Whitcher, Stan Lee and Jon Favreau serve as executive producers. Marvel's "Avengers: Age of Ultron" opens in U.S. theaters on May 1, 2015.