The duo are joining a lineup that includes such names as Alan Arkin, Jack Black, Billy Crystal, Zach Galifianakis and Jean-Claude Van Damme, all of whom have bit parts in the story which sees the Muppets reunite to put on a show in order to save their movie studio from a developer.
James Bobin is directing the pic, which is currently shooting in various locales around Los Angeles. Jason Segel, who wrote the script with Nicholas Stoller, is the human lead while Amy Adams, Chris Cooper and Rashida Jones are among the human actors in key roles.
The roles the duo are playing are being kept under wraps.
Gervais, repped by WME and United Agents, was last seen in Night at the Museum: Battle of the Smithsonium.
Blunt, repped by CAA and Ken McReddie Associates, next appears in Gulliver’s Travels with Jack Black.