Quiet bookworm of the Sailor Senshi Ami takes pride in her studies, but a rival naming himself Mercurius is suddenly outscoring her on the national exams. Combine this with a sudden love letter and a youma feeding on Ami's stress over the whole situation, and Sailor Mercury finds herself in a huge pinch. (Source: ANN)

The first episode is a summary of SM, SM R and SM S, the second episode is about Haruka and Michiru on a cruise ship. They fight one of the SuperS enemies and decide to leave this villain to the classical Sailor Team. (That's an explanation why the outer Sailor Team doesn't appear in this season.) In episode 3 Chibiusa uncovers one of her classmates as a monster and fights her with the Sailor Team in a vampire castle.

Everywhere around the world, the children sleep. Unaware of danger lurking in the shadows. But tonight, a strange darkness floats in the wind. And the children, one by one, begin to disappear. It seems to be a supernatural force that feeds on their dreams. The evil queen, Badiyanu, and her loyal fairies assist in using the Black Dream Hole to swallow the earth. It is up to Sailor Moon and the Sailor Soldiers to prevent the approaching Darkness. (Source: ANN)

Mayumi Doujima promises her parents that she will give up on her dreams of becoming an astronaut on her 14th birthday if she cannot find a star she once saw long ago. Overhearing her troubles, the eccentric Manabu Soutouin offers to help her search for the star alongside the rest of Yubiwa Academy's mysterious Pretty Boy Detective Club, whose rules are as follows: Be pretty, be a boy, and be a detective! However, Mayumi is unique—she can see many things that ordinary people cannot. Her eyesight allows her to see the tiniest of details, from people approaching her at a distance to hidden traps that would otherwise go undetected. When the search for the lost star begins to sour, the Pretty Boy Detective Club end up entangled in something far beyond what they ever imagined.