TV series
A lawyer with a ten-percent winning rate is caught up in a murder case and becomes the notorious and genius con artist, Big Mouse, overnight. In order to survive and protect his family, he tries to reveal the true colors of the privileged people involved in a huge conspiracy.
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Checked Jul 22, 2026
A lawyer with a ten-percent winning rate is caught up in a murder case and becomes the notorious and genius con artist, Big Mouse, overnight. In order to survive and protect his family, he tries to reveal the true colors of the privileged people involved in a huge conspiracy.
Cast, crew and production details
Lee Jong-sukPark Changho
YoonaGo Miho
Kim Ju-hunChoi Doha
Kwak Dong-yeonJerry
Yang Kyung-wonGong Jihoon
Ok Ja-yeonHyeon Joohee
Oh Eui-sikKim Soontae
Kim Jeong-hyeonJung Chaebong
MBCSouth Korea
Studio DragonSouth Korea
AStorySouth KoreaWatch options above are for the show and may vary by season or episode.
Episode 1
Changho, who has no money and is about to lose his wife, receives a call from the mayor of Gucheon.
Guest stars Park Sang-hyeon, Park Yong, Lee Sang-kyung, Shin Seung-yong, Lee Byeong-cheol, Seo Myung-chan, Lee Dong-kyu, Yoon Kwan-woo
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Episode 2
Changho is charged with drug abuse and locked up in Gucheon Prison.
Guest stars Jang In-ho, Song Ha-Rim, Hong Joo-hyung, Min Sang-woo, Jin Yong-uk, Lee Joon-gyu, Yoo Su-bin, Kim Do-wan
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Episode 3
Changho needs to maintain recognition as Big Mouse to protect Miho.
Guest stars Park Jeong-bok, Kim Si-young, Heo Woong, Jin Mo
Where to watch Big Mouth
Episode 4
Gong Jihoon makes a bet with Changho to find out his true identity.
Guest stars Park Jeong-bok, Heo Woong, Jin Mo, Lee Young-jin, Han Gi-joong, Ma Jeong-pil, Kim Bum-suk, Kim Won-suk
Where to watch Big Mouth
Episode 5
Jihoon approaches Miho to find Seo Jaeyoung's thesis. Does Miho know Changho's true identity?
Guest stars Shin Seung-hwan, Shin Duk-ho, Hong Seok-bin
Where to watch Big Mouth
Episode 6
Miho joins the prison medical volunteer program to meet Changho.
Where to watch Big Mouth
Episode 7
Jaeho warns Changho to stop looking into Seo Jaeyoung's thesis. Miho is suddenly attacked.
Guest stars Pyo Young-seo, Park Kwang-jae, Kim Jung-don, Yoon Hwan, Park Hui-eun, Goo Si-yeon, Lee Seung-joon, Kim Do-young
Where to watch Big Mouth
Episode 8
Changho is in a mental hospital. Will Changho be able to hide his identity in a state of confusion?
Guest stars Park Kwang-jae, Kim Min, Bae Ho-geun, Jang Joon-ho, Shin Na-ra
Where to watch Big Mouth
Episode 9
Changho stands as an informant in Seo Jaeyoung's trial, and Jihoon and Jungrak search for Changho.
Guest stars Lee Taek-geun, Kim Do-young, Bae Ho-geun, Sun Yul-woo, Kim Kwon, Lee Jae-woo, Park Ji-ho, Cho Yu-jin
Where to watch Big Mouth
Episode 10
Changho calls out Big Mouse, and an unexpected character turns up at the agreed time.
Guest stars Lee Sang-kyung, Shin Seung-hwan, Han Sa-myeong, Lee Jang-ho, Gi Eun-you
Where to watch Big Mouth
Episode 11
Changho shifts the power dynamics in the prison to pressure Big Mouse. Doha plants a new warden.
Guest stars Cha Si-won, Lee Kyu-sub, Jeon Jae-Hong, Park No-gyeong, Mi Seok, Choi Yoon-bin, Oh Ki-hwan, Jun Sung-won
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Episode 12
The warden plans to use the prison riots to take out Changho and Miho.
Guest stars Cha Si-won, Kwon Ban-seok, Lee Kyu-sub, Gi Eun-you, Jeon Jae-Hong, Lee Hyun-gul, Lee Yun-sang
Where to watch Big Mouth
Episode 13
The hot-plate restaurant is in ruins. The agitated Changho meets someone unexpected there.
Guest stars Jung Hyung-suk, Jang Ui-don, Jung Jae-jin, Jin Tae-yeon, Woo Hyun-seo, Baek Seung-ik, Im Jae-geun, Lim Yong-soon
Where to watch Big Mouth
Episode 14
Changho makes a tempting offer to Chairman Kang. Doha conspires with Yoongab to get rid of Changho.
Guest stars Lee Do-hye, Jang Ui-don, Jung Jae-jin, Sung Nak-kyung, Jung Dong-geun, Lee Young-jin, Han Gi-joong
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Episode 15
Changho prepares for the full-fledged elections against Doha, but Miho's health is in trouble.
Guest stars Kim Gyeong-min, Lee Do-hye, Jung Dong-geun, Hwang In-jun, Han Dong-kyu, Park Sang-jong, Kim Do-Hyung
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Episode 16
The TV debate begins, and the smoking gun that will bring down Choi Doha is at Miho's fingers.
Guest stars Kim Gyeong-min, Lee Do-hye, Hwang In-jun, Han Dong-kyu, Park Young-bok, Yoon Bok-sung, Min Eung-sik
Where to watch Big MouthEpisode information updated Jul 22, 2026
