It's been a long time since Jigen, Goemon and Fujiko last heard from Lupin; then one day, they each receive an invitation from Lupin for a reunion aboard the luxury liner Sirloin.

An old man who supposedly knows the secret to Hitler's legacy lives in East Germany within the Berlin Wall; Lupin tracks the old man down, but the old man can't recall anything about the legacy.

At Loch Ness in Scotland, the mysterious monster Nessie reveals itself from the lake, charmed by Fujiko's singing; seeing this, Doctor Oz decides to use Fujiko to capture Nessie for his own gain.

Fujiko and a mystery man have an enticing job for Lupin: stealing a ton of gold bullion from a Swiss bank renowned for its tight security.