Stiles and Theo team up to find Lydia who is somewhere in the tunnels. Theo has Lydia's scent, so Stiles has no choice but to go with him.
Scott and Liam turn to Meredith for help. After a walk in Meredith's mind, Scott has a new game plan. Find the hellhound. Find Lydia.
Meanwhile, Malia needs the help because Kira's unconscious and still emitting a lot of electricity. Thankfully, the electricity chimera guy (forgot his name) shows up and offers to help if Malia will take away Corey's pain. It works!
Lydia manages to use her banshee scream to blow off half of Valak's head. That's our girl. Stiles and Theory arrive just in time to help Lydia walk out.
Meanwhile, Mason's outside of Eichen, and he's in charge of getting everyone out of there. Luckily for him, Hayden shows up to help him out.
Scott and Liam find Parrish and tell him the plan. It's Hellhound mode time! The Hellhound finds Lydia just in time. Tracey tried to ruin the day by taking Lydia, but Natalia Martin put an end to that real quick.
They manage to get her to Deaton's just in time. It wasn't looking good, and for awhile I was yelling at my TV, but Lydia pulled through thanks to her mom and Stiles.