Deep under the city of Niagara Falls lies the largest tunnel ever constructed. It's days from completion. It's already a target for terrorism. When operational the tunnel will supply millions of gallons of water to the Robert Moses Hydroelectric Power Plant, a facility that provides energy for the upper east coast of the United States and is a key part of the United States electrical grid. Jack and his team arrive to inspect the security of the project before it goes into operation, but ISIS has other plans. Taking over the facility, the terrorists now hold the staff and the entire eastern seaboard hostage. Jack finds himself cut off and trapped. He has two problems: he's 400 feet underground, and one of the hostages is his wife. The terrorists think they have the upper hand, but they don't know Jack.