Kang-il is a rescue firefighter whose wife died while he was helping someone else in an accident. Struggling with guilt for being unable to save his wife, Kang-il frantically jumps into dangers to rescue others. Mi-soo, a doctor at a general hospital, makes a misdiagnosis and gets sued by the patient's husband when the patient ends up slipping into a critical condition. In danger of losing her medical license, Mi-soo's lawyer advises her to convince Kang-il to testify against the patient's husband for an assault that occurred while the husband was in grief. She sets out to win Kang-il over by "dating him."
However, Kang-il is not one to fall for Mi-soo's schemes and gives her the cold shoulder. At last, Mi-soo volunteers to be a paramedic to work alongside Kang-il and get closer to him.
Despite the initial cat-and-dog relationship, as they struggle through the dangerous rescue sites together, they gradually fall in love. But their relationship falls apart since Kang-il cannot let go of the memories of his late wife and furthermore when he finds out the real reason why Mi-soo approached him. Kang-il is driven once again into chasing after the most dangerous rescue sites, while Mi-soo can no longer stop him. Then one day, when Kang-il gets buried under a collapsed building, Mi-soo runs after him not knowing whether he will survive