Doctor Who: The Mind Robber (1968)

To escape from the volcanic eruption on Dulkis, the Second Doctor uses an emergency unit. It moves the TARDIS out of normal time and space. The travellers find themselves in an endless void where they are menaced by white robots. Having regained the safety of the TARDIS, they believe they have escaped — until the ship explodes. They find themselves in a land of fiction, where they are hunted by life-size clockwork soldiers and encounter characters like Rapunzel, the Karkus, and Swift's Lemuel Gulliver.

Unfortunately the movie Doctor Who: The Mind Robber is not yet available on HBO Max.