Cold was humor is pretty grisly stuff. Conceived in the shadow of Hiroshima's mushroom, most of it is as macabre as the chalkings of a condemned man on the wall of his death cell. For almost an hour Mr. Potts Goes to Moscow looks like an exception, juggling atomic weapons with a familiarly deft British touch. Then, as if exhausted by the harrowing task, it too succumbs to the subject matter.

Where it succeeds, the film relies on the audience's tendency to laugh when it feels superior. Like Charlie Chaplin, Mr. Potts is funny because he is pitiful. As a plumber over his head in power politics, he represents all of us who are entangled in a cold war too big for us to understand or control. We laugh because, for once, we see somebody more bewildered and hopeless than we.

For about half the film this comic technique works beautifully. As Mr. Potts blithely bungles into international intrigue completely oblivious of what he is doing, he becomes progressively more pitiful and more comical. George Cole, whose doleful, expressive face is perfect for the part, makes Potts almost Chaplinesque. The beginning is also enlivened by some very funny caricatures of British bureaucrats and civil servants as they frantically try to retrieve the plans for "Project Cataclysm."

Unfortunately, the first half of the film wrings all the humor from Pott's predicament, leaving the second no fuel to run off. The Moscow scenes, which could have been hilarious, are eked out with stock routines which lost their humor three years ago. The only really comic sequence in the second half if Potts' imitation of a Chinese delegate as he escapes through a Berlin Peace Conference.

Among the supporting cast, Oscar Homolko is wonderfully ingratiating as the Community loss who brings Potts to Moscow. The most that can be said for Nadia Gray is that she manages to look well even in the grim garb of the Kremlin.

On the same bill is the loudly-heralded UPA adaptation. On the same bill is the loudly-heralded UPA adaptation nof Edgar Allen Poe's "The tell-tale Heart." Imaginatively interpreted in a sort of restrained surrealism, it is a delight to the eye, but fails to capture the terror and suspense of the original yarn.