Below, the events of the film are told in parallel perspectives through flashbacks and the present; however, the original film is presented in a nonlinear narrative.
Pim and Ploy are twin sisters both conjoined at the stomach. Pim is very sweet, caring, and protective, especially of Ploy, though Ploy's nature is generally harsh and cold. The girls have a very close bond and promise each other to stay together until they die.
While they are staying in a hospital, Pim and Ploy meet a boy named Wee. The girls display mutual affection for him, but Wee only confesses his love for Pim, provoking Ploy's jealousy. After his recovery from an illness, Wee decides that he wants to see Pim one last time before leaving the hospital and visiting the twins' room. As much as Pim wants to see Wee, Ploy refuses to get out of bed in an apparent jealous rage. As Wee gets upset and leaves, Pim, filled with anger and sadness over Ploy's jealousy, demands that she and Ploy be separated. To do so, the twins undergo surgery, which Ploy does not survive. Pim burdens herself with guilt, thinking that if she had not wanted an operation, Ploy would still be alive.
Years later, Pim has married Wee, and the couple live in South Korea. She receives a phone call from Thailand that her mother has had a stroke. When Pim and Wee return to Thailand, a series of strange events begin to happen, and Pim believes that the ghost of Ploy is behind them all. When she tells Wee her theory, he becomes very worried and starts seeking psychiatric help for Pim. But even after the psychiatrist comes to visit Pim, she still experiences the hauntings and what Wee believes to be hallucinations. The hauntings escalate from moving objects and voices to Pim coming in contact with Ploy; Pim hears her breathing on her side while she sleeps, she sees Ploy in the mirror instead of herself, while on an elevator she sees Ploy resting her head on her shoulder, and is nearly drowned by Ploy while taking a bath. Pim feels incredibly guilty and becomes a recluse, with Wee not being very sure about what's wrong with her. However, Ploy's ghost then begins haunting Wee as well.
One night, Wee goes to see Pim's mother, who reveals that Pim is actually Ploy. Ploy had strangled Pim out of jealousy after Pim demanded they be separated. But when Pim dies, Ploy suddenly snaps out of her rage and feels shocked at what she did. She screams for help from her mother, who is devastated over Pim's death and never speaks to Ploy again. To save Ploy's life, doctors had to separate Pim's corpse from Ploy's body. Ploy assumed Pim's identity to be with Wee. It meant that all these years, Ploy was lying to Wee, and it was Pim's ghost that was haunting him and her. Ploy's mother was fully aware of her actions as well but kept silent. Later, it is shown that Ploy killed her mother by disconnecting her oxygen pipe so she could not tell Wee the truth.
Ploy had no idea that her mother had told Wee the truth beforehand. Wee confronts Ploy, and in a moment of guilt, she tells Wee the truth. Wee is shocked and disgusted at Ploy's actions and decides to leave her, but Ploy knocks him unconscious and takes Wee hostage. However, Wee escapes, and the ensuing fight with Ploy breaks out, causing the house to catch fire. Wee throws a shelf on Ploy and escapes. Trapped underneath, Pim's ghost confronts and holds Ploy down, and as the burning debris rains down around them, Pim smiles, and Ploy dies.
Wee visits the twins' grave and takes out Pim's necklace that he had given her as a gift when they were in the hospital. He places it on their tombstone.
Like Pisanthanakun and Wongpoom's previous film Shutter, Alone opened at #1 at the Thai Box Office grossing $960,000 before falling to #2 grossing $411,043. In total the film grossed $2,040,003 in Thailand becoming the 21st highest grossing film of the year. The film fared even better internationally grossing $9,365,071 worldwide out grossing the directors which made all other movies fall behind previous film Shutter.[2]
Geethaanjali (2013), a Malayalam film, was made after the producers bought the rights to remake it. Keerthy Suresh played the twin roles in this film. Although Geethaanjali was a remake, it was promoted as a spin-off of the 1993 Malayalam film Manichitrathazhu.[8]
