Marvel fans are about to enter the "Age of Ultron"

The Joss Whedon-directed "Avengers" sequel has officially begun production, starting today (Tuesday February 11) in Johannesburg, South Africa.

They'll be there for two weeks before moving on. 

The film shoot is causing major traffic disruptions in Johannesburg, according to Independent Online

Principal photography will commence next month at Shepperton Studios in the U.K. Additional footage will also be shot in Italy, South Korea, and various U.S. locations.

"Age of Ultron" reunites Earth's Mightiest Heroes, including Iron Man (Robert Downey Jr.), Hulk (Mark Ruffalo), Thor (Chris Hemsworth), Hawkeye (Jeremy Renner), Nick Fury (Samuel L. Jackson), Black Widow (Scarlett Johansson), Captain America (Chris Evans) and S.H.I.E.L.D. agents Coulson (Clark Gregg) and Maria Hill (Cobie Smulders). 

Newcomers include Scarlet Witch (Elizabeth Olsen), Quicksilver (Aaron Taylor-Johnson) and Paul Bettany (Vision). James Spader plays Ultron. 

Although the plot is being kept mostly under wraps, the upcoming "Captain America: The WInter Soldier" will reportedly lead into the events in "Age of Ultron, " which will serve as the finale to Phase 2 of the Marvel Cinematic Universe. 

2012's "The Avengers" earned over $1 billion worldwide.

"The Avengers: Age of Ultron" opens May 1, 2015.