The Day of the Dead (S02E05)

As the dust settles, the gang find themselves dispersed around the ancient necropolis. And they soon realize they are not alone – the space is crawling with a magical army of the undead. The race is on to find Jason before he falls prey to the flesh-eating monsters. Elsewhere in the cave system, as Jason battles for his life, he finds an unlikely ally in the mysterious Medea. But can he really trust her? (BBC)