 In 2019, Gary becomes the show's main antagonist when he is revealed to be the culprit who caused the death of Alya's sister-in-law, Rana Habeeb (Bhavna Limbachia) upon sabotaging the Underworld Factory roof — in his attempt to sort out his debts to loan shark Rick Neelan (Greg Wood), leading to the collapse of the factory roof and Rana being killed from the incident as a result.The character later killed Rick in self-defense when the latter tried to murder him in the woods, subsequently taking over his criminal empire as a result.Soon afterwards, Gary proceeded to establish a relationship with David's colleague Maria Connor (Samia Longchambon), clash with Rana's brother Imran (Charlie de Melo) over the circumstances behind his sister's death, become enemies with Sarah's boyfriend Adam Barlow (Sam Robertson) after growing jealous of their newfound romance, develop a feud with Maria's love interest Ali Neeson (James Burrows), hospitalise Ali's brother Ryan (Ryan Prescott) after beating him up for unintentionally stealing his money and blackmail his own client Derek Milligan (Craige Els) into partaking with his scheme to invest the factory — which ultimately sparked the events of Derek instigating a lethal Christmas siege that culminates with his own death, though not after accidentally killing Ali's stepfather Robert Preston (Tristan Gemmill) and shooting David's girlfriend Shona Ramsey (Julia Goulding) in the resulting impact.