An imported machine worth tens of millions suddenly breaks down, bringing an entire production line to a standstill and causing enormous daily losses. A repair technician rushes in overnight to investigate. He rejects the distributor's proposal to replace the main control board and uncovers the truth: an incorrectly connected wire from a previous year, combined with a deliberately altered load limit, caused the failure. He works through the night to restore production, only for his employer to suddenly withhold most of his repair fee. Unfazed, the technician completes the job and leaves a warning that the machine must be recalibrated within seven days. With his technical expertise as his trump card, he calmly prepares his counterattack.