Daniel Milton is a surgeon who, driven by personal tragedy, operates an illegal clinic deep below London's Temple tube station for those who either wish to remain outside the system, or for those desperate enough to seek treatment unavailable through conventional means. Aided by disgruntled underground worker Lee and guilt-ridden medical researcher Anna, Daniel's dangerous and unpredictable clientele test his morality to the limit. But if it means he can save the person he loves, it will all be worth it.