The human body runs through roughly 10,000 blinks, 20,000 breaths, and 100,000 heartbeats over the course of an ordinary day, and this film tracks that machinery in action using high-definition footage, medical imaging, and firsthand accounts from doctors and patients. It follows the body through waking, eating, working, and sleeping, pausing on the systems that keep each stage running: the eye's constant adjustments to light, the lungs pulling in air, the heart's rhythm under stress and rest. Surgeons open a patient's skull for brain surgery on camera, and researchers wire up rocker Steven Tyler's vocal cords to measure them in real time as he sings, showing how the folds stretch and vibrate to produce pitch. Along the way the film brings in cutting-edge scans and monitoring equipment to make visible what usually stays hidden: blood moving through vessels, neurons firing, muscles contracting. The effect is less a story than an inventory, a day's worth of biological work most people never notice their bodies are doing.