She is the world's most elite personal trainer. Her clients include two senators, a Supreme Court justice, and the man who is trying to kill her. She trains them all the same way: until they cannot hide anything. Mara Cole, 33, runs APEX — a private, invitation-only training facility in Washington DC whose clients include the city's most powerful people. She is the most sought-after personal trainer in America: her methods are brutal, effective, and grounded in the specific science of what physical stress does to psychological defenses. Her clients tell her things they would not tell their therapists, their spouses, or their confessors — because at the end of a Mara Cole training session, there is no energy left to perform. Three of her clients are dead in eighteen months. The deaths look like accidents. The police see no pattern. Mara sees the pattern — and realizes she is the connection between every victim. Four seasons follow Mara's investigation, conducted entirely from inside her training sessions, as she uses the specific tool she has — the forced vulnerability of extreme physical exertion — to find who is killing her clients and why she is still alive. S1E1 — The Session APEX in operation. Mara training four clients in sequence. The first death reported — ruled accidental. Mara looking at the file. S2E5 — The Pattern Mara presents her pattern theory to Shaw with the client files spread across her office floor. His face when he realizes she is right. S3E8 — The Reveal The Architect's identity. Every earlier scene with them recontextualized. Mara's face when she understands who she has been training. S4E10 — The Last Session Series finale: Mara and the Architect in APEX's main training floor. No weapons. No allies. Just two people who know exactly what the other is capable of.
