Derek makes Erica part of his pack.  She transforms from the epileptic girl everyone makes fun of, to an absolute hottie.  Scott takes out her and Isaac, but Derek stops Scotty and courts Boyd to join the pack as well.

Meanwhile, Jax finds out you can be immune to the bite, and thinks Lydia gave him her immunity.  Later on he realizes that he has some kind of super strength.  Also, Chris starts training Allison to become a leader of the hunters.