Actor Gregg Henry announced on his Twitter page last night that he has been cast in Guardians of the Galaxy, although he didn't reveal which remaining character he will play.

"OK UK hold on, I'm comin'. Joining @JamesGunn again- #Slither #Super- this time for @Marvel #GuardiansOfTheGalaxy. Gonnabegreat!"
Gregg Henry joins <strong><em>Guardians of the Galaxy</em></strong>
Production has been under way since mid-July, but one of the main characters still yet to be cast is Rocket Raccoon. We'll have to wait and see if Gregg Henry is confirmed as voicing this character.

He joins recent addition Vin Diesel who voices Groot, along with Chris Pratt (Star-Lord), Dave Bautista (Drax the Destroyer), Zoe Saldana (Gamora), Michael Rooker (Yondu) and Glenn Close (Nova Prime) in the cast.

James Gunn is directing from a screenplay he co-wrote with Chris McCoy and Nicole Perlman.

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Gregg Henry most recently starred in Season 3 of AMC's hit drama series The Killing, and he also had recent arcs on Scandal and Bunheads. He previously starred in James Gunn's first two features as a director, Slither and Super.