A urethra stone made of pearl is excreted from the captured albino alligator (now in the Tokyo Zoo) that was found in the labyrinth of tunnels under the reclaimed land beneath the SV2 hanger. With the stone being worth over ¥200,000,000, some of the mechanics try their luck to see if there are anymore albino alligators excreting the stones down there. They don't return and nobody is particularly happy about staging a rescue mission to find them, especially after what happened last time. Sakaki wants to seal the manhole up, but Asuma decides to help and ropes in most of Division 2 to help him. Meanwhile Matsui calls Gotoh to tell him Tadayama Fumihiro, the man who lived down there and occasionally stole food from the SV2, has escaped the mental institution he was in and is most likely headed back to the underground passages. This information comes a little to late for the team and they fall prey to most of his traps, causing Ota to accidentally shoot up most of their equipment. Will they ever get out of there alive?
覚えているだろうか?二課デッキの地下に網の目のように広がる下水道、その奥深くから這い出した巨大な白いワニを。今では湾岸の水族館で静かな余生を送るそのワニが、ある日、推定二億円といわれる大真珠を産み落とした。それは、あの呪われし迷宮の扉を再び開く恐ろしい事件の前兆であった・・・・・・。
El cocodrilo albino capturado anteriormente, que ahora se encuentra en un zoo, produce unas perlas muy valiosas. Con la esperanza de poder capturar otro ejemplar, los mecánicos del departamento deciden adentrarse en las catacumbas de la ciudad, pero tras unas horas no hay rastro de ellos, por lo que el equipo de pilotos de Labor decide emprender una misión de rescate.