Eight-Legged Exorcism (S01E03)

After Clint's daughter arrives with a tarantula she won at a science fair, he foolishly decides to name it after a legendary Greek monster. This enrages the vengeful spirit that resides in the creature, and it takes over the tarantula's body. In retaliation, the demon summons an army of spiders to invade the family's house, turning their lives upside down.