Design Defined

Yong-mi, who is suffering from a predicament, overhears Tae-kyung's secret phone call, who is misusing inside information. Faced with a once-in-a-lifetime opportunity, Yong-mi takes a step into the back alley of the financial markets for a 'normal life'.

Soo-ja behaves differently from Yong-mi's expectations, and Yong-mi and In-kyung use the information they obtained after the twists and turns to invest in stocks for the first time in their lives.

As things get worse, In-kyung and Yong-mi decide to leave Bestid to find new jobs. What is even worse, Yongmi is in danger of losing his own children. Yong-mi decides to find out the name of the 3D printer company to bring his children back.

Yong-mi is undecided between the two companies, so what's Yong-mi's choice? In-kyung accidentally gets Tae-kyung's project call, and Yong-mi hides her identity and attends an insider meeting. However, an unexpected person appears.

Yongmi's heart almost exploded when he met grass in an unexpected place. Yong-mi escapes the crisis on his own terms at the insider meeting. Yong-mi, In-kyung, and Su-ja begin a plot to infiltrate the Ilwon Foundation to obtain information.

Yong-mi, In-kyung, and Su-ja, who have successfully completed their first joint operation, are having fun, but shadows of the past begin to fall on Yong-mi.

Yong Mi can't help but smile alone when she is separated from Soo Ja and In Kung; Young Shin proposes a secret project to Yong Mi.

Jan Di asks help from In Kyung in finding Tae Kyung's lost project phone; Yong Mi is invited to Young Shin's house, where she makes the choice she was trying to avoid.

Young Shin tries to make Yong Mi open up by exploiting the gap she was hiding; Soo Ja and In Kyung learn about Yong Mi's condition.

Yong-mi feels threatened by Young-shin, but Young-shin lets Yong-mi out of the house. After fleeing from Young-shin's house, Yong-mi runs to Jan-di.

Yong-mi gets anxious when Song Woo-chang threatens her. Yong-mi finds herself in a difficult situation after being forced to resign.

Yong-mi tries to bring the children, but gives up; Geum Jan-di faces difficulties in her family; Yong-mi, In-kyung and Soo-ja begin a new project.

With Young-shin's appearance, the situation moves forward without knowing what to expect; Yong-mi and Young-shin set a date for each other; Young-shin accepts the offer.

Yong-mi once again tries to confirm the death of Song Woo-chang from Jan-di; Doo-young wants to give In-kyung a special gift, but she's flustered by the unexpected reaction.

Yong-mi provides Woo-chang with a deal; the manipulation of Woo-chang's stock price leaves an unexpected casualty.

Young-shin confronts Woo-chan. Yong-mi goes undercover for the last time to help put an end to the illicit alliance.