Nothing makes mere mortals more nervous than their beloved superheroes at each other's throats, literally. In the new trailer for Marvel's "Avengers: Age of Ultron" we see Hulk (Mark Ruffalo), Tony Stark/Iron Man (Robert Downey Jr.), Black Widow (Scarlett Johansson), Thor (Chris Hemsworth) and Hawkeye (Jeremy Renner) as they struggle with the evil they must fight in the form of Ultron, and with the discord among themselves.

There are plenty of explosions, flipped cars and screaming humans. And the Hulk does his fair share of smashing... everything.

But fans will most likely be hitting the pause button over and over to see Ultron up close and terrifying.

"Everyone creates the thing they dread," the metal mega-villain Ultron (voiced by James Spader) declares in the trailer. "I'm going to tear you apart... from the inside."

As the Black Widow says in the trailer, "Oh boy." We couldn't agree with her more.

"Avengers: Age of Ultron" hits North America theaters on May 1 , and comes to Australia on April 23 and the UK on April 24.