Mackenzie Rhodes is a journalist who Scarlett O'Connor first encounters in the Season Five episode Not Ready to Make Nice when the two of them meet for lunch. The latter is under the impression that she wants to talk about The Exes but she is more interested in getting the scoop on Scarlett's pregnancy and figures out that Damien George is the biological father, revealing that she had an affair with him. Mackenzie then publishes a false story that Scarlett cheated on Gunnar with Damien.
in the following episode Ghost in This House, Scarlett confronts her over the story, saying that she feels sorry for her, which leads to Mackenzie posting more lies about Scarlett. When Scarlett later holds a meeting with fans of the duo in a bid to help them express their feelings of insecurity, Mackenzie shows up and admits that other students picked on her in school due to the fact that she had spinal problems and was required to wear a brace.