Cars are essential tools for spies. Dorothy got permission from the control center to purchase a new car and worked on the specifications. Then the members of the White Dove Squad arrive and use their imagination to design what they envision as their ideal car. Whose ideas will be adopted?

While the funeral of the assassinated Prince Edward, who was the first in line to succeed the throne, is being held, the nobles of the Kingdom of Albion discuss topics such as whether the second-in-line Princess Mary or the third-in-line Duke of Arkham, Prince Richard, will succeed the throne, and how the Duke of Normandy will act.

The story is set in London at the end of the 19th century. A new task has been assigned to Team White Pigeon, a group of spies from the Commonwealth. It is a delivery of a used bookstore owner to the Commonwealth. Ange, Dorothy and Chise successfully recapture the owner, who had been held in a detention center by the Kingdom. Meanwhile, the "spy hunt" became more intense in the Kingdom following an assassination attempt on the queen, and tension is strained at Control in the Commonwealth. Control speculates that the spy who has dispatched to the royal family might be a "double agent." To find out the truth, they order Team White Pigeon to contact with the spy, whose codename is "Bishop." How their new mission will be accomplished? And who is "Bishop"?

Living by the sea, protecting the sea, and journeying across the sea…They’re the BLUE MERMAIDS! Because of a shift in tectonic plates around 100 years ago, Japan lost much of its area to submergence. To preserve Japan’s territories, Coastal Cities sprung up, one after the other. Eventually, they became Marine Cities, and along with the expansion of sea-lanes to connect them, the need arose for a sizable staff to protect the seas. At the same time, maritime jobs were becoming more popular among women. Hence, the BLUE MERMAIDS had become every female student’s dream job.

Schoolboy Hinata has a big crush on his classmate Shigure, but is too shy to tell her. On the day Shigure is leaving, Hinata flies off on the wings of a bird chasing after her to tell how he feels!

After an attempt on King Richard’s life, assassins target Princess Mary, the next in line to the throne. Team White Pigeon must protect her while locating deadly Cavorite bombs — a tough feat when Ange is Princess Mary’s sister in disguise.

Jungle Pocket, an Umamusume who has been racing tirelessly in pursuit of becoming the greatest, is ready to take on the once-in-a-lifetime Classic Triple Crown series. However, standing in her way are rivals from the same generation, whose talent may even surpass her own.

The fourth film of Princess Principal: Crown Handler.