When a student is found dead during a college-based clinical trial for a new anti-depressant, Lewis and Hathaway struggle to determine whether the incident was murder or suicide, and receive little assistance from the institution's evasive psychiatri... (more)c professor. A second student's death then leads to the revelation that the trial's participants are all operating under the influence of mind-altering drug ketamine, and that the lines between love, obsession and madness have become dangerously blurred.

Alex MacQueen, Christina Cole, Douglas Henshall, Fiona Wade, Jack Roth, Lucy Liemann, Nichola Burley, Sam Hazeldine, Thomas Brodie-Sangster