Currently prepping for "Iron Man 2," Robert Downey Jr. and Don Cheadle are also signed for Marvel Studio's "The Avengers."

Marvel Studios announced Tuesday (Oct. 28) that Downey has inked a four-picture deal that retroactively includes the blockbuster first "Iron Man" film and also encompasses the upcoming "Iron Man 2," as well as "The Avengers." It's expected that the final pic in the pact would be "Iron Man 3."

The studio also confirmed that Cheadle will replace Terrence Howard as Jim Rhodes -- best friend to Downey's Tony Stark, as well as the future War Machine -- in both "Iron Man 2" and "The Avengers."

Both deals had long been rumored, but the Tuesday release was Marvel's first confirmation.

"We are very excited about working with the extraordinarily talented Don Cheadle as we expand the role of Rhodey in 'Iron Man 2.' It has already become apparent as we prep the movie for production, that the dynamic between Robert and Don will take 'Iron Man 2' to new heights," says Kevin Feige, president of Marvel Studios, in a statement.

In addition to signing on the two stars, Marvel has Jon Favreau on board for the ongoing franchise. Favreau, who directed "Iron Man" and will helm its sequel, will executive produce "The Avengers."

In case your calendar isn't already marked, "Iron Man 2" has already staked out a May 7, 2010 release date, while "The Avengers," which will bring together Iron Man, Captain America, Thor, the Hulk and more, will be released on July 15, 2011. Both films will be self-financed by Marvel Studios and distributed through Paramount Pictures.