A robot waiting thirty years for a customer to show up sounds like the setup for a joke. It isn't. In five episodes, Planetarian dismantles every wall you built to protect yourself from crying at anime. The planetarium isn't the story, it's an excuse for two people to matter to each other before the world ends, and that matters more than survival ever could.

Thirty years after the Space Colonization Program failed, humanity is close to extinction and a deadly, unending Rain falls across the Earth. Scavengers called Junkers pick through the ruins for goods. One of them, Kuzuya, slips alone into a Sarcophagus City, the most dangerous kind of ruin, and finds a planetarium from before the war. There he meets Hoshino Yumemi, a companion robot who greets him as her first customer in three decades. The projector is broken, so she persuades him to try fixing it so she can show him the stars. The five-episode ONA blends drama, fantasy and science fiction.