from the hospital. When they are back on the ship, Jonas pleads with the captain and Harry Moon to take him to the Mariana Trench. An earthquake has made Jonas realize that Angel hasn't been following the whales, she's been using the Pacific Rim to navigate her way back to the Mariana Trench in order to breed. Later, Jonas and Mac confront Harry, deducing that he was responsible for cutting the line to his raft. Harry reveals that he is with the CIA and was assigned to make sure Jonas didn't reveal the location of Devil's Purgatory. Finally determined to figure out what exactly Singer is up to, Terry uses Sergei's keycard to access the high security laboratory aboard the Benthos. She is quickly caught by Singer and he reveals that he's really after helium-3, a rare isotope he hopes to use to create the world's first fusion reactor. Terry deduces that because of the unique economic zoning the Mariana Trench falls into, Singer couldn't legally mine the gas, so he used the Tanaka Institute and built his fleet of submersibles to legally enter the trench under the guise of establishing unmanned drones to use as an earthquake detection system. However the problem Singer had been facing was he didn't know where to look for the manganese nodules that contained the isotope. He reveals that the true purpose of the Navy dives that Jonas was part of was to find the isotope. Now, with Celeste having gotten the location from him, the Benthos is finally on its way to the Devil's Purgatory. Masao, having checked himself out of the hospital, flies to Guam to a U.S. Naval base and finds out that the U.S. government helped ensure the lawsuits against the Tanaka Institute went through and made sure they went bankrupt and were desperate enough to go to Benedict Singer for help. The CIA knew what Singer was up to and worked to plant agents within Singer's operation. One was killed aboard the Proteus as well as Heath Williams aboard the Benthos. They ask Masao to step in to get Terry back as well as their agent. Meanwhile, Angel arrives at the Mariana Trench and mates with a male. Having arrived in the Devil's Purgatory, Singer sends the Epimetheus into the Trench to dig for the nodules, Terry joining the trek. Once again the ship is attacked by Kronosaurs, continuing