Ben Kaplan first appeared in Series 6, Episode 5 as a freelance journalist who was in a relationship with Jo Portman. He tried to expose what was going on with MI5's and Section D's activities in stopping terrorism. During the crisis in which three important diplomats are held hostage along with the audience, Ben helps Adam Carter and Ros Myers free the hostages. He is offered a role in the team by Adam but refuses. However, In Episode 9, Series 6, Ben helps the team uncover a plot to assassinate them before they can make peace with the Middle East. At the end of this ordeal, Harry extends Adam's former offer to join the team and Ben accepts. By the start of Series 7, he is working for Section D, replacing deceased agent Zafar Younis. He operates in the field, helping Section D to prevent a Russian attack on London and stop Al-Qaeda terrorism attacks. He goes undercover in the financial markets with Lucas North to stop a financier who is planning to ruin the British economy and help protect a 16-year-old boy targeted for assassination by a rogue MI6 officer. In Series 7, Episode 7, Section D's boss Sir Harry Pearce is accused of being an FSB mole who has been passing secrets from MI5 regarding Operation Sugarhorse. Some of the section's contacts were assassinated; Harry sent Lucas to Moscow to find an asset, who tells Lucas to find a package in a bar. When Lucas finds the package, it shows a photo of Connie James, Section D's analyst, and Bernard Qualtrough, Harry's mentor, and proves that Connie is really the mole in MI5, not Harry. Lucas calls Ben and tells him this. Ben stashes a form he finds in the paper archive proving that Connie is the mole, but Connie appears in the paper archive to assist Ben in finding the form. Connie sees Ben put the form into his pocket. Before Ben can leave the archive to warn Ros and the rest of the team, Connie uses an underwire from her bra to slit Ben's throat, taking the form from his pocket as he dies in a puddle of his own blood. Ben's dead body is found later by the team. Ros arrests Connie, and Harry recommends to Home SecretaryNicholas Blake that Ben, for all of his contributions to MI5 and Britain, should be given a Distinguished Service Order.