3600 Detik tells about the life of Sandra (Shae), who changes over night when her parents divorce ; she colours her hair red and also changes her personality. This causes her friends to wanting stay away from her. Her mom (Wulan Guritno) then decides to move to another city with Sandra. At her new school, Sandra gets acquainted with Leon (Steven William), a bright student who is the best of his class. No one wants to be friends with Sandra, because of her strange behaviour, except for Leon. They spend a lot of time together and Leon starts to have a good influence on Sandra. Until one day Leon cannot be reached. It appears Leon has a big secret.