The night before the final

At Bukit Damai International School in Penang, the robotics club kept its most famous member in a glass room behind the science lab. Silver Blaze was a small silver robot that could sort, lift and race through a maze faster than any other machine in the country. On Saturday it would defend its title at the national championship, and the whole school expected it to win again.

On Thursday evening, the club's coach, Mr Stratton, checked the robot one last time. Its case was pristine, polished until it shone under the lights. He locked the glass door, said goodnight to Pak Hassan, the night guard, and drove away.

At ten o'clock, Pak Hassan opened the dinner that the canteen had left for him: a bowl of curry so pungent that the whole corridor smelled of chilli and garlic. Half an hour later, the old guard fell into a deep sleep at his desk.

When he woke at dawn, he felt slow and groggy, as if his head were full of cotton. The glass door was open. Silver Blaze was gone.

Mr Stratton was found an hour later at the far end of the sports field, sitting on the wet grass with a badly hurt wrist. He said that a man in a dark jacket had run out of the lab, and that he had chased him across the field and fallen.

The school nurse tested what was left of the curry. Someone had mixed a strong sedative into it.

The head teacher was completely perplexed. Nothing like this had ever happened at the school. The police were called, and the robotics team, who had worked on Silver Blaze for two years, were angry and disgruntled. They wanted someone to blame, and they wanted it quickly.

Amira, in Year 11, was the only one who asked a quiet question. "The canteen only serves curry on Mondays," she said. "Why was there curry last night?"