Secret (2007) Timeline Explained – Every Event in Order

Xiaoyu explains that she can only be seen by the first person she encounters after traveling through time. When she arrived in 1999 from 1979, the first person to see her was Xianglun, so only he can perceive her. This is why classmates describe Xianglun as always being alone and why Xiaoyu seems to disappear suddenly, she simply becomes invisible to everyone except her chosen first contact.

Foreshadowing: Xiaoyu's cryptic warning that she can only be seen by 'the first person she meets' foreshadows this unique temporal constraint.

• xiaoyu
• time travel
• invisibility
• first person
• school

Xiaoyu traveled forward in time by playing the score called 'Secret' on the oldest piano in the building. She discovered the score hidden in the piano in 1979 and used it to leap forward 20 years to 1999. This time jump is why she appears as a student at Tamkang Secondary School in 1999, even though she originally attended the school two decades earlier.

Foreshadowing: When Xiaoyu warns Xianglun not to play the Secret on the oldest piano, it hints at the instrument's role as a temporal gateway.

• time travel
• 1979
• 1999
• secret score
• piano

The Secret is a piano score that allows the player to travel through time. When played at the right tempo on the oldest piano in the building, it transports the musician either forward or backward in time. Xiaoyu explains that playing it slowly sends a person forward, while playing it fast sends them backward. The melody holds the key to the entire film's time-traveling plot.

Foreshadowing: Xiaoyu's warning about not playing the Secret on the oldest piano foreshadows its dangerous temporal power.

• secret melody
• time travel
• piano score
• music

When Xianglun visits Xiaoyu's home after graduation, her mother explains that Xiaoyu has been ill and dropped out long ago. This is technically true from the mother's perspective, her daughter did become 'sick' (the time travel phenomenon) and effectively left school when she vanished into the future. The mother believes she is referring to a conventional illness, not realizing her daughter has actually jumped forward in time.

Foreshadowing: The timeline shows Xiaoyu growing increasingly withdrawn and skipping classes before her disappearance, which the mother interprets as illness-related withdrawal.

• xiaoyu's mother
• illness
• dropped out
• confusion

Since Xiaoyu can only be seen by Xianglun (the first person she encountered after time-traveling), everyone else at the school perceives Xianglun as talking to empty rooms and spending time alone. His classmates genuinely see no one there when he interacts with Xiaoyu, which is why they describe him as someone who was always by himself.

Foreshadowing: Xiaoyu's explanation about only being visible to her first contact explains this central mystery of the film.

• classmates
• alone
• invisibility
• xiaoyu
• perception

Xianglun realizes the Secret score can transport him through time just as it did Xiaoyu. While the building is being demolished, he rushes to the old piano and plays the Secret from memory, following Xiaoyu's instruction to 'play it fast when I want to go back.' By playing the melody quickly on the oldest piano, he travels backward 20 years to 1979, arriving before the building was constructed.

Foreshadowing: Xiaoyu's instruction to 'play it fast when I want to go back' directly enables Xianglun's temporal journey.

• time travel
• 1979
• demolition
• secret
• piano

During his graduation performance, Xianglun sees Xiaoyu near the door and they share a fleeting smile before she disappears again. This brief encounter confirms to him that she is real and that their connection matters more than the performance. He abandons the stage to pursue her, prioritizing their relationship over the academic milestone, driven by his urgency to find answers about her mysterious nature.

Foreshadowing: The moment foreshadows Xianglun's ultimate choice to sacrifice his present life for a chance at their shared past.

• graduation
• performance
• xiaoyu
• chase
• choice

As the demolition crew begins tearing down the piano building, Xianglun sits at the ancient piano and plays the Secret. The structure crumbles around him as he plays the final notes. Rather than being crushed, he successfully travels backward through time, escaping the collapse by crossing into 1979. The apparent destruction becomes his gateway to the past.

Foreshadowing: The tension of the demolition creates the desperate context that forces Xianglun to attempt time travel.

• demolition
• building collapse
• time travel
• piano

The closing image shows a 1979 Tamkang Secondary School graduation photograph with Xianglun and Xiaoyu standing together. This reveals that Xianglun successfully traveled back to 1979 and was integrated into that year's class. By arriving in the past before the original timeline, he has rewritten their story, they now graduate together in 1979, suggesting he prevented the events that originally separated them.

Foreshadowing: Xiaoyu's statement that she 'can only be seen by the first person she encounters' implies that Xianglun, by becoming that first person in 1979, can now exist alongside her in the past.

• graduation photo
• 1979
• ending
• rewritten timeline

Xiaoyu warns Xianglun because the oldest piano in the building is the instrument through which the time travel occurs. She discovered the Secret score hidden within that specific piano and used it to travel forward. Playing the melody on any other piano would not trigger the temporal effect, and playing it incorrectly on the old piano could have dangerous or unpredictable consequences.

Foreshadowing: This warning directly sets up Xianglun's successful time travel when he later plays the Secret on exactly that piano.

• oldest piano
• secret
• warning
• danger
• time travel

In 1979, Xiaoyu spoke with Xianglun's father (who was already a teacher at the school) and told him about the Secret score and her ability to time travel. She left a message written on the back of the manuscript for him. When Xianglun investigates, his father confirms Xiaoyu's story and provides the crucial manuscript with her message, which gives Xianglun the key to understanding and replicating her time travel.

Foreshadowing: The father's role as a teacher at Tamkang Secondary School in both 1979 and 1999 establishes his position as Xiaoyu's original contact point in the past.

• father
• teacher
• manuscript
• xiaoyu
• 1979

Xianglun passes a note to Xiaoyu asking her to meet in the practice rooms, but Xiaoyu never receives it. Qingyi arrives instead, believing the note was for her. When Xianglun approaches with his eyes closed (possibly imagining Xiaoyu), Qingyi kisses him, thinking it was intentional. The janitor's loud greeting then reveals the mix-up to Xianglun, who rushes to find Xiaoyu but she has already vanished.

Foreshadowing: This misunderstanding accelerates Xiaoyu's withdrawal and foreshadows the tragic miscommunication that drives the lovers apart.

• qingyi
• kiss
• accident
• note
• misunderstanding

During graduation, Qingyi lends Xianglun her bracelet as a token of luck for his performance. When Xiaoyu glimpses him from the doorway, she notices the bracelet on his wrist. This creates误会 (misunderstanding) in her mind that Xianglun has moved on to Qingyi, contributing to her decision to retreat further and ultimately vanish. The bracelet becomes a symbol of his perceived betrayal.

Foreshadowing: This moment of jealousy intensifies Xiaoyu's emotional withdrawal and sets up the tragic separation before Xianglun learns the truth.

• bracelet
• qingyi
• jealousy
• graduation
• misunderstanding