When the Pie Was Opened (1941)

Surrealism, avant-garde sound montage, and irreverent wit might be the last thing you'd expect from a government-sponsored film about wartime cookery. But director, artist, animator and all-round firework of a man Len Lye specialised in the unexpected. A simple tale of a mother cheering up her daughter with a pie from her rationing-stricken pantry (interestingly the war is never directly referred to) is skilfully crafted into a work of real artistic depth, while retaining an unpretentious charm.

Unfortunately the movie When the Pie Was Opened is not yet available on HBO Max.