Sarah, Felix and Mrs. S take a trip with the hopes of tracking down the Castor Original. But they are not alone. Back home, Donnie tries to save the family business when Pouchy defects, but it is Helena who manages to secure a "full refund.” Meanwhile, Cosima becomes suspicious of Shay, and Delphine takes the matter into her own hands. But nothing will ever be the same again when Leda finally finds what they've been looking for.