Question: Kim Yoon-seok stars in a 2015 South Korean supernatural mystery thriller film based off what award-winning short film?

Context paragraphs:
Punch (2011 film): Punch () is a 2011 South Korean coming-of-age film directed by Lee Han about the budding mentor-mentee relationship forged between a rebellious high school student from a poor household (Yoo Ah-in) and his meddlesome homeroom teacher who moves in next door (Kim Yoon-seok).

The Classified File: The Classified File () is a 2015 South Korean period crime drama film directed by Kwak Kyung-taek based on a real-life 33-day kidnapping case in Busan in 1978.  It stars Kim Yoon-seok and Yoo Hae-jin in the lead roles.

The Priests (film): The Priests (; lit.  Black Priests) is a 2015 South Korean supernatural mystery thriller film written and directed by Jang Jae-hyun, based on his award-winning short film "12th Assistant Deacon".

Kim Yoon-seok: Kim Yoon-seok (born January 21, 1968) is a South Korean actor.  Kim's theater background first led him to be cast in minor roles on film and television.  His breakout role came as the villain in gambling film "" (2006), but it was his performance as an ex-cop turned pimp in surprise hit "The Chaser" (2008) that brought him acting awards and stardom in his forties.  Kim has since become an acclaimed leading actor, along with Choi Min-sik, Song Kang-ho, Sol Kyung-gu, Hwang Jung-min, Ha Jung-woo, in terms of acting talent and box office guarantee in Korean cinema, in films such as "Running Turtle" (2009), "The Yellow Sea" (2010), "Punch" (2011),"The Thieves" (2012), "" (2013), "Sea Fog" (2014), "The Classified File" (2015) and "The Priests" (2015).

1987 (2017 film): 1987 is an upcoming South Korean political drama film directed by Jang Joon-hwan, starring Kim Yoon-seok, Ha Jung-woo, Yoo Hae-jin and Kim Tae-ri.

Love Me When You Can: Love Me When You Can () is a 2006 South Korean morning soap opera broadcast by MBC starring Ha Hee-ra, Kim Yoon-seok, Kim Bo-ra and Lee Min-jung.  The series was directed by Jang Geun-soo and Kim Woo-sun.  It premiered on July 17, 2006 and ended on March 9, 2007, airing every Mondays to Fridays at 7:50 a.m. for 169 episodes.

Jang Jae-hyun: Jang Jae-hyun (born 1981) is a South Korean film director and screenwriter.  Jang served as an assistant director on the blockbuster period drama "Masquerade" (2012) before breaking out with the short "12th Assistant Deacon" (2014) which won Best Film in The Extreme Nightmare section at the 13th Mise-en-scène Short Film Festival, and Best Director Award (Korean Competition For Shorts) at the 15th Jeonju International Film Festival in 2014.  Based on the award-winning short, he made his first feature film "The Priests" (2015) - a supernatural mystery thriller, which was a hit with more than 5.4 million admissions.  Jang said ... "I got a weird feeling when I saw a priest waiting anxiously for someone on the other side of a fast food restaurant window.  "The Priests" started then."

Odd Thomas (film): Odd Thomas is a 2013 American supernatural mystery thriller film based on Dean Koontz's novel of the same name.  It is directed, written and co-produced by Stephen Sommers and stars Anton Yelchin as Odd Thomas, with Willem Dafoe as Wyatt Porter and Addison Timlin as Stormy Llewellyn.

Running Turtle: Running Turtle () is a 2009 South Korean film about a countryside detective trying to capture a legendary prison breaker.  Released on June 11, 2009, it was directed by Lee Yeon-woo and starred Kim Yoon-seok and Jung Kyung-ho.

The Chaser (film): The Chaser () is a 2008 South Korean action thriller film starring Kim Yoon-seok and Ha Jung-woo.  It was directed by Na Hong-jin in his directorial debut.  Inspired by real-life Korean serial killer Yoo Young-chul, the film was shot on location around Mangwon-dong in the Mapo District, Seoul.

Supporting paragraphs: Kim Yoon-seok The Priests (film)
Answer: 12th Assistant Deacon