|Family|| Leo Chapman (deceased) |
|Portrayed by||Pia Miller|
When Kat moved into the caravan park, she quickly gained the attention of Brax and Ash, but they decided to steer clear of her on discovering she was a police officer. Kat had been transferred to the local station for a fresh start after turning a blind eye to a colleague she was in a relationship with sending an innocent man to jail, where he was killed. One of her first duties was to arrest Brax, who was prime suspect for the murder of Dean Sanderson. She carried out the initial interview and passed on Ash’s theory that Sam Kennedy was the true culprit to the local police, who didn’t think it worth investigating. After Brax was charged, Kat began to suspect he was planning to leave town in breach of his bail conditions and began making spot checks on the house to make sure he was still there, despite Senior Sergeant Emerson warning her not to act without authorisation. She tried to get Ricky to admit what was going on but instead Ricky decoyed her while Brax slipped away. She met Nate and later had to question him about the bus crash caused by his vehicle; Nate became defensive but Kat assured him he had done nothing wrong. Kat found a security camera photo proving Brax had left town but Kyle used her past to try and pressure her into keeping quiet and Nate also stuck up for Brax. She eventually agreed to turn a blind eye, admitting she thought Brax was innocent but could do nothing to get the case reopened. She later found the stolen money hidden at Angelo’s which ensured his conviction.
She was convinced by John to read the riot act to Jett when he stole a surf club buggy but was unable to help him when the teens tried to stop a mural being cleaned off the surf club wall, since they weren’t breaking any laws and a talking to had no effect. She was a support to Phoebe when she was stalked by Ryan Kelly, sheltering her at the caravan park and helping her take out a restraining order, although she was unable to charge him. She steered Ryan away from the surf club when he seemed ready to approach Phoebe again. When Phoebe was kidnapped, Kat picked up on the fact Ryan had struck while Kyle was away; she found a security camera in her room and traced the signal, going with Kyle and Ash to rescue her. She was initially vague about Ryan’s fate until Kyle insisted Phoebe need to know, prompting Kat to tell her that he was in a secure psychiatric facility in another state.
Nate confided in her about his divorce from Sophie. She began having dinner with Nate and after their second date they slept together. However, she made a quick exit the next morning without having breakfast with him. Chris quickly picked up on it, but when he made a comment about it Kat threatened to arrest him for defamation if he said anything to anyone. She told Nate that she didn’t feel able to be a police officer in a town where everyone knew her business and broke things off. Despite this, they went back to his place for another liaison, but when Matt came home unexpectedly and she had to pretend she was booking Nate for speeding it confirmed her belief that nothing more could happen. She tried to chat to Nate at the hospital while attending a car accident but he brushed aside her mixed messages. Hannah, who Nate had confided in, dropped hints to Kat that people would accept her as she was. She proposed a friends with benefits arrangement with Nate and they went to a motel room together. She confided in him that she had joined the police because one of her brothers went off the rails and joined a gang after their father died, and the police helped him.
Martin Ashford (Ash) imminently begins to have a crush on her.
After two weeks in the Bay, Katarina begins a secret relationship with Nate Cooper. This remains a secret until the Colour Run which is held in honor of Maddy. Nate & Kat have a race and after Kat beats Nate across the finish line, the ladies in the Diner start gossiping about them, which results in Katarina ending things with Nate.
After Phoebe and Kyle break up, Phoebe and Kat begin to drink until they both notice that they ended their relationships for tiny reasons. After Katarina asks Nate to take her back she gets rejected and so does Phoebe.