Carlotta Patterson (Lina Roessler) is the titular hidden villainess of "Carlotta's Way", episode 4.04 of Republic of Doyle (airdate January 27, 2013). She was the wife of businessman Joseph Patterson and the mother of 8-year-old Scarlett Patterson (who was Joseph's stepdaughter).
During the episode, Scarlett was kidnapped and being held for ransom, with the abductor eventually being identified as Joseph's driver Griffin Daniels. Over the course of the investigation being done by the Doyle family, Carlotta and Joseph's marriage was shown to be tense, with Joseph blaming Carlotta for Scarlett's kidnapping due to her having been watching her at the time of the abduction and Carlotta accusing Joseph of hiring Griffin for protection when going to strip clubs.
But as revealed in the episode's climax, Carlotta had been involved with Scarlett's abduction, having conspired with Griffin to commit the kidnapping. Griffin was also revealed as Carlotta's lover, with Carlotta being driven to formulate her daughter's kidnapping after Joseph found out and made plans to divorce her and leave her with no money. Carlotta's plan hit a snag, however, when the ransom drop-off resulted in the briefcase of money falling into a random car, leading to Griffin going against his and Carlotta's plans and eventually kidnap Joseph when he tried to give him a new ransom.
Carlotta was revealed as Griffin's lover and conspirator when Rose Doyle discovered that the two had been staying at the McKeon Motel, finding their names in the reservation book. Carlotta later appeared as Jake confronted Griffin as he was preparing to make off with Scarlett, with Griffin ordering Carlotta to get Scarlett and go. Carlotta instead pleaded with Griffin to stop as he and Jake continued to struggle, stating that she hadn't wanted the plan to go the way it had. Constable Monica Hayward soon after arrived and apprehended Griffin, with Jake's father Malachy releasing Joseph from Griffin's van before Jake revealed Carlotta as Griffin's accomplice. Carlotta went on to confess fully, claiming she would've ended up on the streets when Joseph divorced her and that Griffin refused to release Scarlett when she asked him to after the botched ransom drop-off (with Griffin blasting her for trying to pin all the blame on him). Carlotta then begged the Doyles to let them walk away now that Scarlett was safe, only for Griffin to tell her that she was going down with him as he and later Carlotta were handcuffed and arrested.