The Last Crayon (2014)

Five elementary school students join the choir:Ting, Hei her brother and Fun are from Mainland China; Kathy is returning from L.A.,and the 'detective' Nam is a Hong Kong local. Hospitalised after food poisoning, the suspect points to the tofu brought by Ting's mom. Incidentally the destination of the choir's visit is the tofu production base. During a field trip, they get lost in the rural hills and have to face hunger, fear and death. By accidental they find out Kathy's crayons can be burned as candles---their only hope. But as the crayon sticks dwindle away into the night, it becomes clear that if all were to survive, one of them has to make a sacrifice.....