( CNN ) -- When a film cast includes names like Ben Stiller , Robin Williams and Owen Wilson , a bit of improvisation on set is to be expected . Ben Stiller and the gang are back in `` Night at the Museum : Battle of the Smithsonian . '' `` I think the movie is really only 25 percent scripted , maybe even less than that , '' said Shawn Levy , director of the new film `` Night at the Museum : Battle of the Smithsonian , '' which boasts those comedic actors and several others . `` It just so happens that the scenes that get some of the biggest laughs are the improvised scenes , so it feels like more than that , but we had a very good script and it 's still very much there . '' The sequel to 2006 's `` Night at the Museum '' welcomes back the trio and director as well as other original cast members , including British actor Ricky Gervais , while also adding fresh faces such as Hank Azaria ( as a villainous pharaoh ) and Amy Adams ( as Amelia Earhart ) . Watch the group laugh about the film » . The new romp features Stiller 's character , security guard Larry Daley , in action at the Smithsonian , where some of the pieces from the Museum of Natural History -- the setting for the original movie -- are now being housed . Story writer Robert Ben Garant said watching the actors take the script and run with it was painless . `` It 's always hard to watch bad actors improv on your skit , '' Garant said . `` But when it 's Ben Stiller and Jonah Hill and Hank , it 's such a pleasure because it always starts with the idea of our script and sometimes they stick to the words , but most of the time they do stuff much , much funnier and weirder . It 's really great to watch . '' Owen Wilson is back as Jedidiah the miniature cowboy , who is now being held hostage at the Smithsonian . Azaria turns up the mean as Kahmunrah , the bitter brother of the pharaoh from the last film . Azaria said he thoroughly enjoyed his turn as the film 's resident bad guy . `` When the villain is this ridiculous , it 's fun , '' Azaria said . `` When he actually has a sense of humor and self-awareness , and goes from frivolous to really mean bully . '' `` In the end I had to be forced to do the mean stuff because I always wanted to do the silly stuff , '' he added . `` But watching it ... I enjoyed the mean stuff the most. `` Even with the good times on set , filming at the iconic Smithsonian was a monumental task , given that it was n't always closed while the actors worked . Stiller said the crowds who watched the movie making magic were respectful and quiet during filming , often breaking into applause after a scene . `` We were n't really doing much , it was just the best audience in the world , '' he said . `` So it was sort of like doing a live show at the Smithsonian . '' Funny man Stiller even got to monkey around on set -- literally . In this film , there were two simians that took on the actor in a scene that found him getting the short end of the branch . `` I basically get slapped by both of them , but I am not allowed to slap them back because of animal rights , so I have to slap a dummy or a tennis ball when they 're off-screen , '' Stiller told the British newspaper , The Mirror . `` It 's a weird experience . '' Robin Williams , who is recovering from heart surgery , said he was excited to return as Theodore Roosevelt -- this time with a twist . `` I got to play two versions of Teddy Roosevelt , '' Williams said . `` One , the Teddy that was in the first movie and the other was kind of a brassy , bitchy Teddy and the one that 's a bust of Teddy Roosevelt . '' With so many comics on board , it ca n't help but be a zany ride . Wilson said he believes those good times will translate to the audience . `` Shawn was really great about kind of letting people try things , '' he said . `` So it just had that kind of spirit on it where everybody was having a good time . I think you kind of feel it when watching the movie . '' Director Levy said the actors were n't the only ones who had fun . It 's not every day a crew has access to the secret life of a museum , especially the Smithsonian , and Levy immersed himself in the privilege . `` It 's such a fun world to explore , it 's so dynamic , and the possibilities are literally endless , '' he said . `` I just love telling these stories . '' Since filming was such a blast , might there be a `` Night at the Museum 3 '' in the works ? `` Ask me after Memorial Day , '' Levy said , laughing .
` ` Night at the Museum : Battle of the Smithsonian '' reunites cast and crew . Director says he improvised much of the dialogue . It is sequel to a 2006 film . Ben Stiller got into a crime fest with a pair of policemen .