Cage on the Sea (絶海密室, Zekkai Misshitsu, Distant Seas, Locked Room) is a 1998 novel, written by Japanese author Kaoru Ohno about a group of Japanese holdouts on the island of Anatahan in the Pacific Ocean.

During the Pacific War, after three Japanese supply ships are sunk off the shore of Anatahan, the survivors are taken in by Kikuichiro Higa and Kazuko, his live-in wife, who have a small coconut plantation on the island.

Junzo Itami, tries to maintain discipline, but as the group endures U.S. airstrikes and food shortages order begins to break down.

Soon the men become obsessed with Kazuko, the lone woman on the island, and a vicious dynamic sets in among the survivors.

The novel received a favorable review from Tim Hornyak in The Japan Times.