1x23 - Littlest Pet Shop

Sunil and Vinnie hear howling noises coming from inside the pet shop, and suspect that their friends have turned into werewolves. When Mrs. Twombly finds she has been outbid at an online auction for a highly coveted doorknob by her rival, Fisher Biskit, she takes Blythe and herself for a visit to his mansion to find its whereabouts.