Air traffic controller Nick Jensen's life is in a shambles. His wife Lisa has died following a horrific automobile wreck and the authorities suspect foul play. He finds evidence suggesting Lisa, a Pentagon auditor, had discovered potentially treasonous material on a fellow employee's computer, a man who also winds up dead.

Desperate to escape the pain, Nick throws himself into his work and is on duty at the radar ATC facility serving Boston's Logan Airport on the night U.S. President Robert Cartwright is scheduled to fly into Boston. Armed terrorists storm the facility, killing the security staff and taking Nick's fellow controller hostage as he works.

Nick escapes capture, but with time running out, must use the information from his murdered wife to unravel the terrorists' plot and stop an assassination while outnumbered, unarmed and on the run...