A Roman bath architect gets yeeted through time into Japanese onsen culture, and somehow the show understands that both civilizations just really, deeply love hot water. The gimmick is absurd and never changes, but it's executed with such infectious joy that you're laughing at Lucius's bewildered face the entire time. It's three episodes of pure comfort wrapped around one joke that the show swears by completely, no irony, no winking, just a man discovering that across 2,000 years and an ocean, humans want the same thing: to soak and forget the world exists.

Lucius Modestus is an architect of public baths in ancient Rome, but he has run dry of fresh ideas and is out looking for work. His gloom worries his friends, who drag him to a busy bathhouse in the hope he will relax. When he ducks his head under the water to escape the noise, he finds a hidden passage that carries him to a bathhouse in present-day Japan. Each trip hands him inspiration far beyond his era, and back home he tries to rebuild what he saw with Roman means, usually ending up with rougher versions. His inventiveness may still be enough to win over the public and restore his standing. The short comedy plays on the bathing traditions of two cultures, Roman and Japanese, that both hold the bath dear.