Hardy and Hemmingway investigate when a young girl reports her father missing following a break-in at his home, and later discover that he was kidnapped by the attacker. After initially suspecting an ex-employee of his company, Hemmingway later discovers that one of the man's former school friends decided to take his revenge on him following a sustained campaign of bullying. However, as she and Hardy close in to make an arrest, the suspect flees onto a bus, where he holds Hemmingway and six other passengers hostage at gunpoint. Meanwhile, Fletcher and Keane arrest a youth for shoplifting and dealing in stolen CDs on the basis of video footage found on a mislaid mobile phone.