The upcoming mystery drama “A Day” is about people who wake up to find themselves locked in what seems to be an eternal time loop.

“It’s a painful day that you hope will end but never ends,” said director Jo Sun-ho (“Killer Toon,” 2013) at the film’s press screening in Seoul Wednesday.

“It’s a day where you have to watch your loved one die over and over again, where someone has to kill over and over again.”

The film has been invited to screen at the Sitges International Fantastic Film Festival, set to take place in Catalonia, Spain on Oct. 7-16. 

Jo said he wanted to differentiate the film from other time travel-themed stories through a “tightly-weaved plot.”

Kim Myung-min, who recently starred in the television period drama “Six Flying Dragons,” plays a world-famous doctor who volunteers to work in Third World countries, Joon-young. His busy schedule forces him to neglect his 12-year-old daughter Eun-jung, played by Jo Eun-hyung. Joon-young witnesses his daughter being fatally hit in a car accident on her way to meet him on her birthday, and he frantically wakes up to discover that the events were a dream.

The dream repeats itself everyday as Joon-young struggles to save his daughter, whose continuous death reveals a dark sin in the esteemed doctor’s past, in different ways each time.

Kim said it was particularly difficult to do the same scenes in slightly different ways.

“I thought a lot about how to express the subtly different emotions for each repeated day,” he said.

He expressed confidence in the film, saying its plot “does not follow the commercial hit equation of Korean films.”

Byun Yo-han, who also starred in “Six Flying Dragons,” plays ambulance driver Min-chul who discovers he is stuck in the same time loop as Joon-young.

He too suffers the death of a loved one for days on end, and the two characters desperately attempt to devise a plan to change the sequence of events, only to fail each time.

Various layers lurk beneath the repetitive setup, according to Byun.

“It is a mystery thriller but in the end it is about making amends and how to forgive.”

The film has a running time of 90 minutes and is distributed by CGV Arthouse. It hits local theaters on June 15.

By Rumy Doo (doo@heraldcorp.com)