By March 1942, the Japanese army had conquered Singapore, and Japan's navy had vanquished surface forces from the United States, Great Britain, Australia, and the Netherlands in the Battle of the Java Sea. From that point, no non-Japanese surface ship was safe in the waters of the East Indies. Practically unopposed, the Japanese transported a substantial army as well as sea and air forces to their base in Java—Surabaya. From there they reportedly planned to invade Australia, and it appeared nothing could stop them.
Except that someone at Pearl Harbor with authority and foresight, Pacific Fleet Commander-in-Chief Admiral Chester Nimitz, ordered a squadron of submarines to western Australia. One of those boats is the subject of this story.