Here is ABC's official description for the episode: "Emma tries to convince Aladdin to work with Jasmine to help Agrabah, while Regina teams up with Snow and David to free Archie from Zelena. The Evil Queen sows suspicion between Henry and Hook, even as Mr. Gold reminds her of his most important lesson. Meanwhile, in the past, Hook finds himself kidnapped by the mysterious Captain Nemo and Held Captive inside his legendary submarine, the Nautilus."