 Chicago air controller Jack Harris is a wreck with guilt nightmares after a major Transair crash, killing all 174 aboard, gives up the job and designs air control software instead. Five years later, his ex-colleague T.C. Bryant, meanwhile also transferred to Phoenix, desperately asks him to help out short-term, given desperate staff shortage on Newyears eve with a bad storm predicted, after a power cut hits, which is actually the sabotage work of technical whiz John Quinn, who has meanwhile messed up the systems on several airports, so they see their workload multiplied. Colleagues welcome him in very different states of mind but he quickly proves his capabilities, alas then the fatal memories start creeping up again: will his lack of self-confidence cause another drama?