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.

Unaired special of “Himouto! Umaru-chan” included with the manga’s seventh compiled volume. After being tempted by a pillow on the television shopping channel, Umaru has a dream reminding her to appreciate the pillow she has. The next day, Umaru goes with Sylphnford to the convenience store where she tries to win a lottery prize. Later, Umaru and Taihei go wild at a yakiniku restaurant, unaware that Nana is at the next table over. At the start of October, Umaru and Kirie get into the Halloween spirit early, dressing up in costume and trying various pumpkin-based snacks. Afterwards, Umaru decides to fake a fever in order to skip school, only to be overcome by guilt.

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"?

Unaired special of “Himouto! Umaru-chan” included with the manga’s tenth compiled volume. Realizing it is Taihei's birthday, Umaru asks Nana for advice on what to do for him. Umaru decides to act like an ideal sister and spend time with Taihei, only to discover that he prefers her the way she is. Later, as the girls begin their summer vacation by going to a swimming pool, Umaru wonders if she should stop putting on an act in front of her friends and reveal that she, Komaru, and UMR are the same person. As Umaru becomes conflicted over what will happen if she tells everyone, her friends assure her that she doesn't need to reveal her secrets if it'd just make her suffer. Relieved by the support of her friends, Umaru makes the decision to continue hiding her secret.

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.

In Fujisawa, Sakuta Azusagawa is in his second year of high school. Blissful days with his girlfriend and upperclassman, Mai Sakurajima, are interrupted by the appearance of his first crush, Shoko Makinohara.

The fourth film of Princess Principal: Crown Handler.