SEOUL, Aug. 25 (Yonhap) -- Losing a beloved child is perhaps the most unbearable agony a parent can endure -- so deep that no single word exists to describe a parent who has suffered such a loss.

"The Journey to Gyeong-ju," follows Ok-sil (Lee Jung-eun), a hard-working mother of four young women, who grapples with such a tragic fate after her youngest, Gyeong-ju, is murdered during a school trip to the historic city of Gyeongju.

The film begins eight years after the crime, known as the "Gyeongju high school student murder case," robbed the family not only of its youngest daughter, but also of its father, who takes his own life while fighting for justice for his daughter.

In sharp contrast to the weight of the insufferable tragedy, "The Journey to Gyeong-ju" opens on a surprisingly upbeat note, as Ok-sil and her three remaining daughters -- Jang-ju (Kong Hyo-jin), Young-ju (Park So-dam) and Dong-ju (Lee Yeon) -- set off on a road trip.

Clad in matching T-shirts, the family travels aboard a battered yellow minibus to the city that bears the name of their late sister.

This still, provided by Lotte Entertainment, shows a scene from the film "The Journey to Gyeong-ju." (PHOTO NOT FOR SALE) (Yonhap)

Their goal is clear: to take revenge with their own hands on the man responsible for Gyeong-ju's death.

But things do not go according to plan for the clumsy yet good-hearted would-be killers, who panic at the sight of an insect inside their vehicle.

This comical yet chaotic ambience drives the first half of the film as the mother and daughters encounter one mishap after another on their way to Gyeongju.

It is in this first phase that director Kim Mi-jo builds the distinct personalities of the three daughters -- wishy-washy but supportive firstborn Jang-ju, smart but cool-headed law graduate Young-ju and hot-blooded former pro-wrestler Dong-ju, who is the loose cannon of the family.

The mood dramatically shifts when the ruthless Sang-hyun (Byun Yo-han) -- whom the family paid to have kidnapped and anesthetized in order to ultimately kill him -- escapes from a shed at the cabin in Gyeongju where they are staying.

This still, provided by Lotte Entertainment, shows a scene from the film "The Journey to Gyeong-ju." (PHOTO NOT FOR SALE) (Yonhap)

Showing no remorse, Sang-hyun kills a civilian and police officers he encounters. He then disguises himself as a police officer to harm Ok-sil and her daughters before they get revenge on him.

On top of Sang-hyun's presence lurking around the family, the long-suppressed rift of emotions that had run deep inside the family following Gyeong-ju's death -- guilt, sorrow and angst -- begin to surface.

In a situation where they must come together to survive a merciless criminal, the family members go their separate ways as emotions erupt and they hurl thorny words at one another.

Following a tumultuous series of incidents, the family ultimately reunites, their bond stronger than ever after they have come to accept Gyeong-ju's death and recognize how they have dealt with it in their own ways.

This still, provided by Lotte Entertainment, shows a scene from the film "The Journey to Gyeong-ju." (PHOTO NOT FOR SALE) (Yonhap)

In this sense, "The Journey to Gyeong-ju" stands in contrast to the recent wave of popular action-packed Korean films and dramas that prioritizes cathartic revenge plots.

But what it lays bare is the deep but real struggles the family of crime victims go through in everyday life, long after the court proceedings have ended.

Nor does the film offer any sympathy to the criminal. By withholding his personal background that might be used to explain his motives, it keeps the focus solely on the victim and her bereaved family.

Against this backdrop, actor Lee Jung-eun delivers a poignant performance as a mother on the brink, living with an aching "fire" in her heart since the loss of her youngest daughter.

The mishmash of genres of black comedy, suspense and drama, which becomes clearer with the drastic tonal shift following the reveal of Sang-hyun's face, may feel overly abrupt to viewers who expect a more comic story after watching the first half.

"The Journey to Gyeong-ju" is set for release Wednesday.