Aimes was part of Michael's plan to kill the Pope. When the original plan failed, however, Aimes, along with several other Catholics working alongside Michael, killed Giancarlo's guards and impersonated them. When Jack Bauer and Harry Driscoll identified Mark Gelson as he was about to kill the Pope, a gunfight ensued. Aimes was one of Michael's men killed during the gunfight, according to Pembrooke.
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