Knotheart is a gray and white patched tom with a scar on his chest.
- He is seen grooming his fur in the warriors den, glad that he had been chosen to be the deputy of Plumestar. He plans to himself to last as long as possible, hoping to eventually succeed Plumestar one day.
- After Plumestar returns from getting her nine lives, she gives Knotheart the apprentice Thriftpaw to mentor to warriorhood. When she is done with her ceremony, he gets up from where he is, and pads over to his apprentice, touching noses with her, wishing her good luck. However, he spots Dandelionpaw on her father, Curlewfeather, and demands her to stop it at once. He then turns back to apprentice, and tells her that they would get things done. He then adds that he wants her to be the very best she could be, remembering how his first apprentice had died accidently falling off a cliff. Thriftpaw is excited to be his apprentice, stating that she was happy to be his apprentice, and she wanted to be just like him.
- Twitching his whiskers, Knotheart replies that he understood, nothing that he used to be just like her when he was her age. He then asks if they should get on with their training, adding that they didn't have much time. Knotheart then takes a pawstep back, and it is noted that he had expectations for his apprentice, as he did not want her to fail.