Four join 'Night At The Museum' sequel

Christopher Guest has joined the cast of Fox's Night At The Museum sequel, says The Hollywood Reporter.

Guest, known primarily for his work as a "mockumentary" filmmaker, will play Ivan the Terrible in the big-budget comedy. Joining him in the cast are Jon Bernthal (Al Capone), Bill Hader (George Armstrong Custer) and Alain Chabat (Napoleon).

Currently shooting in Vancouver under the direction of Shawn Levy, Night At The Museum: Battle Of The Smithsonian reunites cast members Ben Stiller, Robin Williams, Ricky Gervais and Owen Wilson from the first film.

Amy Adams and Hank Azaria also feature in the sequel, which is scheduled for a May 22, 2009 release.