The title “Hyde Park on Hudson” tells you the main thing you need to know: The most important character is a household. President Franklin D. Roosevelt, his mistresses and the King and Queen of England pop up in different rooms, but not one of them is more than a supporting character in this atmospheric, well-acted, pointless story.

At first, the film seems to be about shy, lonely Daisy (Laura Linney), a distant cousin of FDR’s who lives in Duchess County, N.Y., near his country home. FDR’s mother invites Daisy over to “cheer up” her son, who takes her riding in his open-topped car and eventually adds her to his string of carnal conquests.

Then King George VI and Queen Elizabeth (Samuel West and Olivia Colman) arrive to seek FDR’s support – and, by extension, America’s financial backing – for Britain’s imminent war against the Nazis. (The movie never specifies a time, but it’s set in the summer of 1939. In real life, their majesties had already spent time in Washington, D.C., with the Roosevelts.)

Then FDR’s secretary (Elizabeth Marvel) becomes prominent, as she reveals that her boss’ needs must be met by multiple women – herself included. Finally, Daisy listlessly takes center stage again.

Director Roger Michell (“Morning Glory”) and writer Richard Nelson (whose other film feature is the 1993 “Ethan Frome”) keep the tone light, declining to dig under any of the character’s skins.

FDR remains an avuncular philanderer, at ease with the humble and the great. For the first time in 35 years onscreen, Bill Murray completely loses himself in a character: He captures FDR’s toothy smile, insouciant manner and canny ability to size others up, but he’s never given a chance to vary this light, jovial tone.

George and Elizabeth begin as twits, giving limp royal waves on a country road to tractor drivers who don’t look their way. They whine about decorations on a bedroom wall – propaganda cartoons from the War of 1812 that mock the British – and sniff at the prospect of eating hot dogs and seeing Indians beat tom-toms. (We are repeatedly asked to laugh at their upper-crust pronunciation of “hawt dawgs.”) The movie eventually humanizes them, but they’re still caricatures.

If you ponder the film for more than a few minutes, it reveals a weird, pathetic side.

FDR’s mom pimps for her son: She knows everything that goes on at Hyde Park, so she must know she’s leading Daisy into his bed. Eleanor Roosevelt, FDR’s wife, is implicitly a lesbian jealous of her husband’s sexuality. (And Olivia Williams is too good-looking to play this homely lady.)

Whether America ought to back England against Hitler depends less on the prospects for western civilization than on whether George VI turns out to be a decent guy. Daisy believes being one of FDR’s cling-ons is better than any other life she’s likely to get; I think we’re supposed to be cheered by this, but I wasn’t.

On the other hand, why think? The film bounces jauntily along, never less than handsome to look at, and the actors all do fine jobs. The women are especially poignant or funny, with Linney leading the way as a wallflower given a chance to bloom. But a movie about any of these people in depth would have been more compelling.