[On the one hand, Lester's film A Funny Thing Happened on the Way to the Forum has] the framework of [Bert] Shevelove and [Larry] Gelbart's Broadway hit, its slow fuse Jewish-American humour, its carefully set up jokes about dithering middle-aged men and bullying wives let loose in Brooklyn-on-Tiber. This humour takes time: above all, time for the actors to build contact with the audience. On the other hand, there is Richard Lester's style, glancing, cool, nerveless, and dependent on perpetual motion. Lester seems to circle the comedy, jabbing, weaving, feinting, hardly landing a solid punch.
What works with the Beatles, in fact, won't do when the actors are a generation older, and physically more resistant to the whole idea of being stood on their heads…. Style, as the film progresses, becomes more and more like conscientiously strenuous decoration, an effort to manufacture exuberance. Why take a shot upside-down; or flick through half-a-dozen of the briefest, most eye-straining glimpses of the characters; or turn a song into a display exercise for the camera, shuffling through locations as though they were playing cards? The only answer would seem to be, why not….
Too much of the [film] is either frantically diversified action (a chariot-chase, for instance, which gathers speed without comic momentum), or an effort to lift the text almost bodily across the footlights…. And the film slips away down the gap between two entertainment formulas.
Penelope Houston, "'A Funny Thing Happened on the Way to the Forum'," in Sight and Sound (copyright © 1967 by The British Film Institute), Vol. 36, No. 1, Winter, 1966–67, p. 47.