Carol Hall was a recurring character on Beauty and the Beast. She was a superhuman, and portrayed by Natasha Henstridge.
Carol and her husband, Bob, are introduced as Homeland Security agents who take over the case of Agent Thomas' murder from Catherine Chandler and Tess Vargas. However, they later catch Catherine & Vincent Keller investigating the case without permission. Vincent tells them that someone tried to kill Catherine, as well. Carol figures out that Vincent & Catherine are engaged, and empathizes with them. Carol decides to team up with them, and convinces Bob to. Vincent & Catherine tell them that Thomas was killed by a sniper. They figure out the building the shooter was in, and Carol & Catherine go undercover to see if they can find evidence of the killer. Though security finds them, the two are able to escape with the evidence.
Carol is impressed with Catherine fighting off the security, and advises her not to lose that part of herself when she gets married. After the evidence they obtain is destroyed by the same sniper, Vincent & Catherine decide to tell Bob & Carol about how someone is experimenting on innocents to turn them into superhumans. Just before they arrive, though, Catherine & Vincent find out that there are two shooters, as the bullet that killed Thomas was re-directed by another bullet in mid-flight. They then discover that Bob & Carol are not DHS agents, and realize they're the killers. Bob & Carol plant a bomb in order to kill Vincent & Catherine.
Vincent realizes that the serum they were injected with helps Bob & Carol speed up the brain's processing. When Bob & Carol later show up, Vincent & Catherine confront them about who they're working for, and why they agreed to team up. When the two sides refuse to reveal what they know, they start fighting each other. Carol & Bob almost kill Catherine & Vincent, until Vincent reveals himself as a beast and fights off Bob. Catherine then fights off Carol, knocking her out. Carol & Bob then run away, knowing the bomb is about to explode. Vincent, though, figures out their plan, and he & Catherine manage to escape.
Bob later tries to kill Catherine in order to finish the job, but Carol stops him, saying they need Catherine alive to capture Vincent, reminding him they can't go back to whoever injected them empty-handed. Bob agrees, and lets Catherine go.
Carol is later seen trying to get Catherine's attention in order to draw her out and away from Vincent. She decides to plant evidence that will lead Catherine into a trap. However, Catherine figures out what Carol has done just as she gets there. Carol tries to kill Catherine, but misses. Catherine later comes after Carol, who knocks out Catherine and taunts her that she can anticipate her every move. Catherine, though, has found out Carol can only see it in the light, and manages to turn off the power, taking away Carol's ability. She's able to subdue and arrest Carol, but Tess informs her that Bob has gone after Vincent, and Carol tells Catherine she won't be able to save him.
Carol realizes that Catherine & Vincent are dependent on each other the way she & Bob are. Catherine, though, tells Carol that Vincent is capable of taking care of himself, but Carol is doubtful, saying he needs Catherine there to keep him from going "primal." Catherine tries to get Carol to admit who she's working for so Catherine can help. However, Carol says their only chance of being helped is if Vincent turns out to be the beast they believe, and if they hand him over to their boss. However, Vincent manages to kill Bob and escape. Before Tess and Catherine can tell Carol what happened, she figures it out from the look on their faces. Heartbroken over losing Bob, Carol commits suicide by stopping her heart.