Yeong-ro, a fresh and lively freshman at Hosu Women's University, falls in love at first sight with Soo-ho at a group blind date.

Soo-ho, comes into the window of Room 207 in Women's University Dormitory and collapses. Yeong-ro and others plunge into great confusion over him.

Yeong-ro takes care of the injured Soo-ho in the attic and tries to find a way to send him out of the dormitory without being noticed.

Soo-ho, who leaves the dormitory, begins to secretly move again. Meanwhile, Lee Kang-moo secures decisive evidence of Soo-ho's whereabouts and pursues him.

Soo-ho negotiates with the head of the National Security Agency to escape the dormitory with his teammates.

Turning a blind eye to Yeong-ro who feels betrayed, Soo-ho continues the hostage crisis.

When Soo-ho realise Yeong-ro is the daughter of the head of the National Security Agency, he has no choice but to use Yeong-ro to make it out alive.

Soo-ho's heart breaks because of Yeong-ro. Meanwhile, the tension builds up as the hostage crisis makes it to the news nationwide.

Yeong-ro does not believe in Soo-ho's sincerity and eventually works out an escape plan with Kang-moo.

When the anonymous reveals their identity, Han-na carries out Kang-moo's order and moves to catch the secret evidence surrounding the hostage crisis.

Finally facing the cruel truth surrounding the hostage crisis, Soo-ho joins hands with his enemy Kang-moo and suppresses Cheong-ya.

With the situation getting worse, Soo-ho and Yeong-ro depend on each other more. Soo-ho and Kang-moo expose the scheme behind the presidential election.

Soo-ho comforts Yeong-ro who no longer trusts her father. Students are confused as to which side they should trust.

Soo-ho is heartbroken to see Yeong-ro struggling with guilt after hearing the news about her father. Soo-ho and Kang-moo start distrusting each other.

Giving up his hope in Cheong-ya, Soo-ho has no choice but to accept the head of the National Security Agency's proposal.

Soo-ho, who left Yeong-ro, stands at the crossroads of fate just before returning to his hometown.