The team find a mask of an ancient tribal deity at the Yeveh Burial Grounds in West Africa and put it in a box at the request of their client, Pere Martin. The team get away from attackers and return the mask, which has stored up hundreds of years of pain and fear and seems to have a strange influence on MacKenzie. Robbers attack and take the mask in its box while Mac obsessed about finding it. One of the thieves is compelled to don the mask and kills the other while the team closes in but the possessed thief escapes. The voodoo expert they're consulting, Charlotte, is actually the one seeking the mask – when they get it, Mac dons the mask and tells the others it's lost while turning increasingly violent. The possessed thief turns himself in and tells the guys Mac has the mask. Charlotte gets word and steals the mask then kidnaps Martin and a sacrificial knife. The team finds her and stops the ritual, and the mask is lost in the waters, apparently for good . . . or until it finds a new wearer.