Beom Soo, Jae Yun, Ju Wan, and Tae Hwan undergo pre-training and are appointed as police officers. They are dispatched to the Nowha Police Station of Wando Coast Guard. The members go out to the field on their first day and assist in inspecting the Soando Fishing Boat Fire Case.

As they had an incident on their first day, they don’t expect anything to happen. However, that’s not the case. They go to rescue a stranded man. Even when they’re going to the rescue, it’s not a peaceful journey.

A mysterious object is found in the ocean. A high seas watch is in effect. The guards clean up the beach and underwater, finding lots of garbage. The day seems to go smoothly when detectives come and ask for cooperation on arresting a wanted man.

The guards are on a long chase for a man on the wanted list and experience their first stakeout. They visit the historical Soando Island to deliver materials, where they learn the meaningful and patriotic history of the island.

The coast guards display great teamwork as they work through inspections and emergencies. They also visit a small island filled with elderly people to sanitize their homes against COVID-19.

The work at Nowha Station doesn't slow down, even until the four coast guards’ last day. They bid farewell to their home and the station. They hold an emotional discharge ceremony on Wando Island.