The telepicture is scheduled for broadcast Nov. 6.
Harmon plays Minneapolis Deputy Police Chief Lucas Davenport.
"Davenport doesn't need his job; he could have retired long ago with the money he made designing computer simulations. But Davenport loves what he does just as much as he loves nice suits, fast cars and women. When a cop is shot after witnessing the murder of the wife of a local real estate lawyer, Davenport is called to the scene. The cops quickly zero in on the husband as the prime suspect until a team of FBI agents... descends on Minneapolis with evidence linking the crime to elusive hit woman Clara Rinker, (played by) Tatiana Maslany," the cable network said in a synopsis Thursday.
Harmon serves as executive producer on the TV movie along with Michael Jaffe and Howard Braunstein of Jaffe-Braunstein Films Ltd.
The actor is best known for his work on TV's "NCIS."