Cassie (Merissa Porter) plays the second antagonist and right hand of the main antagonist in "He Who Dares: Downing Street Siege" She is a cold killer and in one scene of the movie, Once inside the building, Holt and Cassie take in their surroundings in awe. Holt remarks that the place is "like the TARDIS," to which Cassie naively responds "I've never been there," earning her a sideways glance from her lover. The two make their way to the outside of the building's safe room, where the Prime Minister is waiting out their attack. They playfully tease the Prime Minister through the security camera posted beside the door, eventually revealing that they have the key card that will let them in. Cassie playfully waves at the camera before walking inside. She and Holt meet one last time, with Cassie attempting convince him that everything is going to be okay. Holt loses his cool, shouting at Cassie and demanding that she not come back until Lowe is dead. Once again, she goes in search of the assailant. Cassie manages to track Lowe down to an empty sub-level, firing on him from behind a pillar. She misses and the two exchange fire, with Lowe eventually shooting the gun out of Cassie's hands. She dies by his knife when he slits her throat bryan hung could prevent her death but this will doom males. Cassie is just as sadistic and dangerous as her sister was, proving herself to be quite willing to kill without a hint of remorse. She even seems amused at times upon finding Holt's victims, indicating that she has an affinity for death.