Walt Disney Studios have just announced the formal start of production on Captain America: The Winter Soldier, the second installment of the Star-Spangled Avenger's film franchise.

According to a statement, filming has commenced in Los Angeles, with production also including locations in Cleveland, Ohio, and Washington D.C.

Based on the best-selling comic book series by Ed Brubaker, here's how Disney describes the plot:

“Captain America: The Winter Soldier will pick-up where Marvel’s The Avengers left off, as Steve Rogers struggles to embrace his role in the modern world and teams up with Natasha Romanoff, aka Black Widow, to battle a powerful yet shadowy enemy in present-day Washington, D.C.”

Robert Redford will star in the film as S.H.I.E.L.D. Agent Alexander Pierce, according to the press release. The character in the comics was an analyst-turned-field agent who later served as an aide and bodyguard to Nick Fury. He's been described in the film as the head of S.H.I.E.L.D.

EmilyVanCamp's Sharon Carter is referred to as Agent 13 in the press release, meaning they may try to keep her identity quiet for the first part of the film. Hayley Atwell is confirmed as returning to reprise her role as Peggy Carter.

Captain America: The Winter Soldier is set for release in the U.S. on April 4, 2014.