If Hyde Park on Hudson proves nothing else, it does show that Bill Murray is no Ralph Bellamy. After years as a motion picture supporting-actor and B-movie lead, Bellamy began an adjunct career portraying Franklin D. Roosevelt. Over more than a quarter of a century, he was FDR on stage, screen and television. And at least cosmetically, he was quite convincing.

In Roger Michell’s new movie, Murray is the president in the summer of 1939, prepared to maneuver to provide assistance to Great Britain, which faces almost certain war with Hitler’s Germany. This sounds sober-minded and seriously portentous, but Hyde Park is scarcely a rigorously instructive history lesson. It’s sentimentally inclined, a little naughty, and seems to be aiming for gentle, tolerant amusement at the very modest expense of Roosevelt and his entourage.

The two story lines involve the visit of the United Kingdom’s George VI and Queen Elizabeth, come to subtly argue their country’s cause in the US, and the president’s illicit affair with his fifth or sixth cousin Daisy Suckley (Laura Linney). Over the course of a couple of days, these two plot vectors cross paths. When they do, the movie is at its most amusing; but the filmmakers seem to have no particular point to make or insight to propose, save that FDR was a man of restless, intense amatory tendencies, wheelchair and crutches or not. At times, Hyde Park slightly resembles a French bedroom farce.

The movie is ostensibly told from Daisy’s viewpoint (her diaries were posthumously discovered in 1991), and she narrates, but there are a number of incidents here that she couldn’t have known about. Moreover, despite Linney’s skills, this Daisy just isn’t very interesting.

Murray’s FDR is more so, but we don’t get much nearer to anything substantial, despite Murray’s often lightly charming performance. He’s reasonably presidential, but it’s hard to imagine him intoning “The only thing we have to fear is fear itself.” On the other hand, it’s even harder to feature Ralph Bellamy crawling across a golf course armed with anti-gopher weaponry in Caddyshack. This may or may not equal a wash, but Hyde Park amounts to no more than a small, mildly piquant, and only loosely fact-based historical footnote.

Watch the trailer for Hyde Park on Hudson