The drama is set at the fire department's communication command center, depicting the "reality" of the command dispatchers who are on the "front line" of maintaining lives with a phone. The command dispatchers respond to emergency reports and issue appropriate ambulance and fire truck dispatch orders. They are a group of fire and emergency experts with various skills. They use communication skills and medical knowledge to listen to "voices" every day and save "life" with "voices" in order to save "life" in danger.