Episode 3 (S04E03)

Two familiar faces from the past make an unexpected return: Katrina and Hector's old acquaintance, Louis. However, their motives are far from noble. Katrina aims to win Archie back, while Louis has his sights set on taking control of Glenbogle by marrying Molly. Lexie feels threatened by Katrina's arrival and, distressed, decides to leave and head over the hills, prompting Archie to search for her. As tensions rise, everyone gathers as the happy couple prepares to tie the knot.