Avengers assemble! ‘Avengers: Age of Ultron’ is sure to be one of the biggest movies of 2015 – if not THE biggest. On April 13th, the film’s many stars gathered in Hollywood for the world premiere. Click on for loads of photos.

As Black Widow, Johansson was the surprise MVP in last year’s ‘Captain America: The Winter Soldier.’ Her role is even bigger in ‘Age of Ultron.’

The dapper Iron Man star has plenty to smile about: the Downeys are one of Hollywood’s most powerful couples – Susan’s a producer.

The ‘Thor’ actor is an Aussie while the ‘Furious 7’ star hails from Spain, but this husband-and-wife team radiate pure Hollywood glamour.

There’s nothing Hulk-like about Ruffalo as he happily signs his autograph for a fan.

Here we have a hirsute Captain America at right. Unfamiliar with Kevin Feige? He’s only the president of Marvel Studios, and his movies have earned over $8 billion.

Hawkeye vamps with the former S.H.I.E.L.D. bigwig. (Before any rumors start flying, Smulders’ husband Taran Killam was her date at the premiere.)

Marvel’s big-screen Nick Fury grabs a selfie with some Iron Man statues, including the much-buzzed-about “Hulkbuster” suit.

The voice of Ultron himself graces the red carpet with his longtime companion.

She may play Scarlet Witch in ‘Age of Ultron,’ but the actress skips the red and goes straight for the white and blue in this elegant number. Hulkbuster approves.

Also new to the Avengers franchise, the actor plays the lightning-fast Quicksilver. His wife (pictured here) directed the 2015 hit ‘Fifty Shades of Grey.’

The British thespian, who has voiced Tony Stark’s Jarvis computer system since 2008’s ‘Iron Man,’ finally gets his turn on screen as the heroic Vision.

Ant-Man crashes the party! Rudd’s own Marvel movie will be released July 17th. Yes, that's ‘Iron Man’ director Jon Favreau at left.

Speaking of directors, the man behind the first two ‘Avengers’ films looks as proud – and as exhausted – as you’d expect him to be.

You can’t have an ‘Avengers’ premiere without the Marvel master, still going strong at 92. Will he have a cameo in ‘Age of Ultron’? Count on it, true believers.