Tom Card's murder
Riley ran the operation to find Michael and take him down. After Michael was seen choking out a hotel worker on a security camera, Riley ordered a team to sweep that floor. Instead of finding Michael, they found the unconscious worker and what looked like another worker, which was really a disguised Sam Axe, checking on him. Sam told them that he saw the guy take the stairs and helped the man even more.
After Michael escaped through the garage, a member of the team told Riley that, while they don't know how he got to the garage, they do know that he didn't use the stairs. Upon hearing that, she went to go see Sam, who was helping the worker into an ambulance. After introducing herself, she told Sam that the man they were after escaped. She asked Sam again if he took the stairs, which Sam confirms he did, unaware that she knew otherwise. She thanked him for his help and asked his name. Sam introduced himself as Charles Finely, but Riley warned him to stop lying to her, and that she knew who he really was. Upon that, Sam was taken as her hostage.
After following Michael to a dock, Riley sent her team after him, but she then ordered her men to stand down and let him go, after Jesse Porter and Fiona Glenanne held her at gunpoint. They, along with Sam and Michael, took Riley to a lake and left her there. Before leaving, Michael told her that Card had been running unauthorized ops and wasn't gonna stop. She first seemed shocked, but then revealed that she didn't care. Seeing them leaving, she vowed to Michael that she would hunt him down.
Riley is a highly intelligent operative. It's been said by Jesse that she's a legend in counterintelligence, writes about half the case-studies used in training, and is better than anyone at "hitting where it hurts."
She has been seen using unorthodox tactics and strategies to help her. After capturing Sam, she discussed, with another operative, places to look for Michael, while Sam was sitting behind them. While thinking of places, Riley, unbeknownst to either her operative or Sam, was watching Sam through the reflection on her virtual map, and only saw him flinch when she mentioned one place, helping her decide where to start.
She is also very observant and has shown the ability to use small details to her advantage, mainly in thwarting plans and strategies. An example is when Michael set up a trap for her in a marina, where she was informed by Sam that he had a boat ready to get out of town. As they were entering the marina, she showed Sam a photo of all the boats in the marina and asked which boat was his and how he knew. Sam showed her a boat and mentioned having fought it out with a barracuda on it while with Michael on a fishing trip a few weeks back. Riley immediately ordered the van they were in to stop upon hearing this and revealed to Sam that his story is impossible, as the photo she showed him was taken six months ago.