The Doctor runs back out to the deck just as torrential rains begin to fall. Henry shouts some nautical instructions to Amy and Rory. They scramble to work the sails, but neither of them really understands what Henry's telling them. Henry tells Moppet to get his coat, so he can get his compass from the pocket, but the jewel-encrusted crown falls out instead. It rolls across the deck. Moppet gives his father a look of disappointment. The Siren vaults out of the crown, singing, and extends a glowing hand to Moppet. "Don't let her take you!" shouts Henry. Moppet staggers toward her. Henry stares for a while instead of doing anything. By the time he makes a move, Moppet has already touched the Siren and disappeared in a puff of black smoke. The Doctor throws the crown overboard and the Siren vanishes. "You couldn't give up the gold, could you?" the Doctor hurls at him. "That's why you turned pirate!" Well, duh. A mast swings loose and knocks Rory into the water. The Doctor stops her from going in after him. "There's only one thing that can save him now!" the Doctor shouts. He opens a barrel of water. The Siren leaps out. The Doctor tells her to go get Rory, so into the ocean she goes. This seems like a pretty shitty plan to Amy, but the Doctor thinks they can reason with the Siren. He thinks the taken men may still be alive somewhere and they have to follow. With their consent, the Doctor pricks Henry and Amy's fingers. Black spots appear on their palms. The Siren comes to claim them.
They awake, soaking wet, on a metal floor. "Where are we?" Amy asks. "We haven't moved," the Doctor says. "We're in exactly the same place as before." They look around and find a wall of windows looking out over the pirate ship's deck. "It's a spaceship trapped in a temporal rift," the Doctor says. He gives them the lowdown on parallel universes sharing the same space in [on?] different planes. The reflections acted as gateways between the realities. The spaceship seems in pretty bad shape, dark and empty with bits of wire and electrical thingies hanging all over. They follow a beeping sound that turns out to have been the distress signal the TARDIS picked up earlier. As they wander through the ship, they can hear the Siren singing. A door slides open, revealing the dead body of the ship's former crew. The skull is elongated and toothy with a bony crest like a dinosaur. The lettering on his spacesuit reads "D.I.H.S."
After a start, the Doctor and friends skirt around the body and make their way into the ship's cockpit. Another dead crewman sits at the controls, slumped over in his seat. "How long has this ship been here?" Amy asks. "Long enough for the captain to have run out of grog," Henry says. He seems otherwise unperturbed. The Doctor sonics the corpse and says the crew were killed by human bacteria. He leans against the console, aiming for a casual pose but landing in a pile of alien snot instead. His hand comes away gooey. Somehow, even though the corpses are dry as the Sahara, the mucus is fresh as a daisy. For once, he's not infatuated with a discovery and wipes his hand down the sleeve of Amy's coat.