Karl Brian Wright was pursued as a "trophy" by Tzim-Sha. He lived at 52 Northover Street, Sheffield and worked for his father's company, Skylark Building Services as a crane operator, despite his fear of heights. He listened to self-assurance recordings to have confidence in himself.
Karl was on the same train as Grace and Graham O'Brien when a gathering coil attacked it in pursuit of him. The Thirteenth Doctor crashed down into the carriage they were in and managed to scare the coil off with an electric cable. He left soon after. However, Tzim-Sha was still in pursuit of him and tracked him down at Skylark, killing Dennis and Dean on the way. He climbed the crane that Karl was in, but the Doctor, Yasmin Khan, Ryan Sinclair, Graham and Grace prevented him from taking Karl. When the Doctor defeated Tzim-Sha, Karl kicked him off the crane as he teleported away and the Doctor immediately reprimanded him for it. (TV: The Woman Who Fell to Earth)
Karl was in Manchester for New Year's Eve 2021, and witnessed ELF Storage being destroyed in a burst of New Year fireworks at midnight on 1 January 2022. Recording the event on his mobile phone, Karl remarked that it was a "good display" and joked that it was just for him. (TV: Eve of the Daleks)