William Marshall, emergency medical technician with Mountain EMS, dedicates his life to providing patient care in Banff National Park. A seasoned medic, 'Marsh' responds to highway wrecks, medical calls, and backcountry disasters with compassion for the injured and a heart for the homeless. Struggling with his past and with a desperately understaffed service, Marsh coaches new-hire Miranda Walker through the learning curve of the job. While answering to an overbearing medical director, and with the local fire department vying to take over Mountain EMS, Marsh and Miranda confront public and private emergencies with professionalism, courage, and humour.

Against the odds, they turn their service and each other's lives around.