Cruise Gear My Car Was In Cruise When It Started Decelerating. When In Gear, It Will Not Move, But The Rpm's Will Rev.

My car was in cruise when it started decelerating. When in gear, it will not move, but the rpm's will rev. - cruise gear

Car is a 2001 Ford Taurus station wagon with 117k miles. The car is very different, unless the engine speed, from a whistle. Ideas?