Gong Ji Hoon's (Yang Kyung Won) plans went downhill as he learned that Park Chang Ho (Lee Jong Suk) is Big Mouse. Everything and everyone around him changes as Park Chang Ho begins to live as the notorious conman in "Big Mouth" Episode 5.

'Big Mouth' Episode 5: Park Chang Ho Gains Power After Revealing Himself as Big Mouse

Mayor Choi Do Ha (Kim Joo Hun) came to inform Park Chang Ho that the names written on the ledger were fake. But it was too late as the lawyer was on his way to meet Gong Ji Hoon.

With the thought that Park Chang Ho was faking his identity, Gong Ji Hoon was confident he would give the wrong names of Big Mouse's clients. Warden Park Yoon (Jung Jae Sung) began to read Gong Ji Hoon's paper where he wrote the real names.

But everyone in the room was frozen after the warden read Park Chang Ho's paper. He mentioned the same names that Gong Ji Hoon wrote.

Due to this, Park Chang Ho gained the upper hand to do what he wanted while inside the Gucheon prison.

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The lawyer began to live as the real Big Mouse, and it would give him the power to resolve Seo Jae Young's case, the reason he was in jail.

Go Mi Ho Discovers Alliance Between Hyun Joo Hee, Park Mi Young

While on her duty as volunteer at the Gucheon University Hospital, Go Mi Ho (YoonA) felt something strange in one of the hospital's rooms. She sneaked at the door and found head nurse Park Mi Young (Kim Sun Hwa) secretly getting blood samples from the sleeping patients.

Mi Ho immediately hid when the head nurse was about to leave the room. To her curiosity, Go Mi Ho quietly followed Park Mi Young until they reached a secret laboratory near the hospital.

Mi Ho tried her best to investigate the place and the possible business happening inside, but Mi Young got out of her sight and saw herself entering one of the lab's facilities.

She attempted to hide, but unfortunately, the guard and Hyun Joo Hee (Ok Ja Yeon) caught her, which made her leave the lab knowing nothing of what was going on.

But there was one thing she was sure of. Joo Hee and Mi Young were doing something suspicious that could be related to Seo Jae Young's case.

Choi Do Ha Confronts Park Chang Ho

Confused and feeling betrayed, mayor Choi Do Ha confronted Park Chang Ho to verify if he was the real Big Mouse. He wanted to know how the convict knew the real names of the clients when the list he gave consisted of fake names.

However, Choi Do Ha failed to secure information from Park Chang Ho. He mentioned Go Mi Ho, but he warned him not to cross the line and leave his wife alone.

Before the episode ended, Choi Do Ha told Mi Ho that Park Chang Ho is Big Mouse. Though she trusted her husband, after hearing the mayor's words, Mi Ho began to doubt Chang Ho.

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Written by Shai Collins.

KDramastars owns this article.