I stared wide-eyed through the glass. Was he about to cheat again?

Deng Chao continued, "I didn’t receive the answer to one of the questions. You failed!"

The student who typed and sent the message cried, "Ah, I made a mistake in one of the numbers! Song Yang, I'm sorry!"

I gritted my teeth, feeling the rage boil up inside. Deng Chao was merely finding fault! At this moment, a puff of yellow smoke spread throughout the sealed room, triggering a bout of coughing fits around the room. "That’s poisonous gas,” I shouted. “Everybody out!"

I pulled a metal bar off the railings and smashed hard into the toughened glass. Only after several hard blows did it start to crack. By this time, the students inside had collapsed to the ground, choking...