Naohito Takayama lands his dream internship with Japan's National Railways, envisioning a peaceful career maintaining the country's beloved trains. Reality hits harder than a speeding locomotive. He joins a security unit staffed with colorful misfits, including Sakurai, whose reflexive hostility toward men makes every shift awkward. Between managing interpersonal chaos and basic patrol duties, a militant faction called RJ emerges with a dangerous agenda: forcibly privatizing the entire rail system. What begins as a cushy summer job transforms into genuine danger as Naohito and his ragtag team scramble to stop sabotage attempts and protect the infrastructure that connects the nation. The show balances high-stakes action sequences with character-driven humor and romantic tension, never letting you forget that beneath the spectacle, these are ordinary people risking everything for something they actually care about. It's part action thriller, part workplace comedy, part romance, all wrapped around an unusual love letter to trains themselves.