When "Once Upon a Time" season 5 returns, the residents of Storybrooke have descended into the Underworld to try to get back Hook. Spoilers, however, are mum on who will die.
Showrunners Adam Horowitz and Edward Kitsis explained to The Hollywood Reporter that the circumstances in the Underworld are pretty much different than in Storybrooke.
"The rules of the underworld - what it means to be there, whether you can leave, how you can leave, where you go - will be explained by Cora," they said.
The synopsis offers plenty of spoilers for "Once Upon a Time" season 5 as it reads, "Emma, Regina, Mary Margaret, David, Robin, Henry and Gold arrive in the Underworld, on a mission to rescue Hook, only to discover that their search will be more difficult than they had anticipated."
"The inhabitants of the Underworld-all souls with unfinished business and many with quite personal vendettas-hound our heroes at every turn. Meanwhile, in an Enchanted Forest flashback, a familiar face from the Evil Queen's past returns to present Regina with the perfect birthday gift."
Among the returning characters in the 100th episode of "Once Upon a Time" season 5 include Peter Pan (Robbie Kay), Cora (Barbara Hershey), Sidney Glass (Giancarlo Esposito), the Blind Witch (Emma Caufield), Blacktooth (Steven Roberts) and the seven dwarves.
Greg Germann, meanwhile, will play Hades, the ruler of the Underworld, and his look is reminiscent of the animated Disney movie, "Hercules," complete with the flaming blue hair. It's not clear if the hair will turn flame red when he becomes angry.
"He absolutely has a surprising connection to one of our cast," Kitsis told Entertainment Weekly.
"Before everyone runs to Twitter to give their opinions on it, he's not related to anyone, but there is a connection," Horowitz added.
"Once Upon a Time" season 5 will return on Sunday, Mar. 6 on ABC. Watch out for more spoilers before then.
