Atlantis has gone zombie. Quick recap of last week's final moments: Dion's dies; Ariadne shoots Pasiphae; then Pasiphae, Medea and Jason get swept deep into the Necropolis when their cliff-adjacent path collapses. Fast-forward to this week: Pasiphae wakes up at the bottom of her fall. She spots a coffin and crawls toward it, uttering some sort of incantation.
Meanwhile, on a level above, Hercules and Pythagoras assess the situation. It's too dangerous to climb down into the area where Jason fell, so they'll have to access his body (which they hope is still breathing) another way. The group begins sneaking through the Necropolis, leaving Dion's corpse behind.
But Dion doesn't stay dead for long. As his former allies creep through the crypt, his undead form comes to life and attacks. "This is kind of like the plot of Dawn of the Dead!" Pythagoras explains. (We're paraphrasing.) Although Hercules manages fell Dion, Diagoras gets bitten. "It's nothing," he says.
Down in the tunnel, Jason sees Medea lying unconscious. He holds his sword to her throat, but doesn't go through with the deed. Instead, he starts walking through the cave—but soon hears Medea being attacked by a group of undead soldiers. Ever the sweetheart, he goes back to save her.
Team Ariadne is once again attacked—seems the zombies die (for good) when pierced through the heart. More zombies attack, and Ariadne gets out her bow and arrow and joins the melee.
On a lower level, Medea is shocked that Jason helped her—Pasiphae always taught her that her enemies would kill her as soon as they got the chance. "She's wrong about many things," Jason said, before asking how Medea knows Pasiphae. "She's my blood," Medea says. And another thing about Pasiphae: she's also the only person who could have risen the dead. Jason and Medea take off through the Necropolis together.
Team Ariadne takes refuge in an upstairs tomb. Diagoras' wound has quickly infected, and Pythagoras needs to treat it. While the men play doctor, Ariadne has a heart-to-heart with Eurydice, Orpheus' wife. Ariadne confides that she knew she loved Jason from the moment she first met him. What if she never gets a chance to tell him? Eurydice is sure that she will.
Things seem to have calmed down, so Hercules urges Pythagoras to rest. As for himself, he's going to keep watch. "Sleeping is for women and babies," Hercules tells Pythagoras, "and men like you." Then he yawns.
Jason and Medea are once again attacked by zombies—and this time it's Medea who saves Jason. When he gets pinned under a particularly angry undead, Medea puts a sword through its heart. Then she heals Jason's broken leg with the help of a quick incantation. Jason is grateful, and tries to point out Pasiphae's flaws. She rose the dead, knowing Medea was in the Necropolis. And she didn't come to save her.
But Medea won't have it: Pasiphae is apparently the only person who has ever accepted her. Medea doesn't want to betray her—even if she already did.
Obviously, Hercules falls asleep. And obviously, Diagoras rises from the dead. So it seems, Pythagoras deduces, that if they are bitten by an undead, they become undead themselves. Which is scary, because Ariadne has a nasty-looking wound on her arm. For a second, things look bleak—but upon examination, Pythagoras says it's just a cut.
However, in all the fuss over Ariadne's wound, they don't notice Eurydice's secret bite. She shows Orpheus, but no one else.
Jason promises Medea that he won't let any harm come to her—she saved his life. But Medea doesn't share Jason's sense of loyalty. "Do not think for one moment that I will betray Pasiphae," she says. Still, when the zombies skulk by, she and Jason take refuge together.
Things are tense with Team Ariadne: Orpheus and Eurydice have been sitting in a silent embrace for ages. Suspicious and worried, Pythagoras initiates a conversation. Maybe he can help in some way? But Orpheus explains there is no way to help—Eurydice has been bitten.
Everyone knows that Eurydice must be killed before she turns, but no one wants to kill their friend. Finally, Ariadne volunteers. She feels it is her duty. Orpheus, however, insists he do it himself. It's a terrible task—but necessary.
Jason finally finds his friends, but they are not pleased to see Medea with him. Hercules and Pythagoras both agree she needs to be killed immediately. But Jason insists that no harm come to her. Besides, there's a reason to keep her around, since she knows how to lift Pasiphae's curse. First step: returning to the place where the spell was cast.
Ariadne asks Jason to hold back while the others go ahead. She explains that she was so worried when she thought he was dead. She can't bear to lose him. "I have faced death, but nothing scares me more than admitting that I love you," she says. Then they kiss.
That was nice. But there's still serious business to attend to. The friends venture deeper into the Necropolis, trying to find the place where Pasiphae cast her spell. Medea explains that the curse was a binding spell—it is tied to ancient symbols, perhaps carved into stone. They must find them and destroy them.
Jason and Hercules go ahead in search of the stone. They locate the tablet, and Hercules finally gets a chance to show off his legendary strength. As zombies close in, he lifts the stone and throws it off the edge of a cavern, cracking the rock and the spell at once. The undead become regular dead, and he and Jason return to the group, triumphant.
For a second, it seems Medea was trustworthy. Jason unties her hands from behind her back, and says he always believed her.
But he shouldn't have. As soon as Medea is free, she grabs Ariadne and stabs her.
Next week marks the finale of the first part of Atlantis season two. Tune in to see Jason get very, very angry at Medea.
Watch full episodes of Atlantis right here!