In a poor neighborhood of Seoul, Pastor Lee Jong-rak has built a padded hatch into the wall of his house. When someone opens it, an alarm rings inside, and someone always comes running. The film follows Lee and his wife as they take in the infants left there, many of them disabled, some left with a note, most left with nothing at all. Cameras go inside the cramped home now doubling as a nursery, crowded with cribs and volunteers, and follow Lee through the paperwork and hospital visits that come after each new arrival. Mothers who use the box are almost never seen, but the film sits with the shame and desperation that drive them to it, and with South Korea's laws and stigma around unmarried motherhood and disability that make the box necessary in the first place. Interviews with Lee lay out his reasoning plainly: he built it so babies would be found alive rather than left on a doorstep in winter.