First-time director Kim Se-hui's “Following” is a mystery thriller that depicts the secretive life of a voyeur and a pretentious attention-seeking social media influencer.

Byun Yo-han stars as real estate agent Gu Jeong-tae, who follows influencer Han Sora, played by Shin Hae-sun. Lee El stars as detective Oh Young-ju investigating a death related to Jeong-tae and Sora.

“Jeong-tae is a kind of character who is really hard to explain in words. That’s why we produced a film on it,” Kim told reporters during a press conference held in Seoul on Wednesday.

Jeong-tae likes to peep into other people’s everyday lives. From stealthily looking at other people’s smartphone screens while on a bus commuting to work to breaking into a stranger's home, he always carries a Polaroid camera. His purpose is to take a photo of an item that he steals from someone's home, something he believes is least necessary for that person.

Attention-seeking social media influencer Sora is Jeong-tae's next target. Munching sausages, she uploads on her social media account a photo of a vegan salad that she pretends to have eaten. In cyberspace, she poses as an animal lover, but that’s all part of her facade.

“Sora’s goal in life is to get attention from others so she can have an influence large enough to impact other people’s lives,” Shin told reporters.

This is the first time Byun and Shin have worked together in seven years: The two appeared as a married couple in another mystery thriller “A Day.”

Kim said she focused on exaggerating the characters while the topic and the background were kept very down to earth.

“I tried my best to dramatize the characters and maximize the negative aspect of human desires. To make sure those who watch the movie can fully immerse themselves in the storyline, I used narration in which Jeong-tae speaks directly to the audience,” she told reporters. She added that the movie proceeds at a fast pace and takes a new turn as Sora is found dead and all of the evidence points to Jeong-tae as a killer.

Byun Yo-han, making his first silver screen since the multiple award-winning historical film “Hansan: Rising Dragon,” said he could not be more confident about the upcoming movie.

“I shot ‘Following’ after ‘Hansan,’ and I received awards (for ‘Hansan’) before shooting ‘Following.’ For me, ‘Following’ is the most anticipated work and I’m confident about the movie, more than (I was with) ‘Hansan,’” he told reporters.

“Following” hits local theaters in May. The exact date of release has not been confirmed.