The airplane was destroyed when it impacted terrain while maneuvering near the Centennial Airport in Englewood, Colo. Night visual conditions prevailed at the time of the accident, which occurred at approximately 1940 Mountain time. The Part 135, IFR flight was en route to Salt Lake City, Utah. The Airline Transport-rated pilot and pilot-rated passenger sustained fatal injuries. According to witnesses and preliminary ATC communications, the airplane departed Runway 35R and executed a climbing left turn to a heading of 280 degrees. During the initial climb, the pilot told ATC he had a problem, was shutting down an engine and needed to return to the airport. Witnesses observed the airplane execute a left turn for a base leg to Runway 35R. The airplane continued past the Runway 35R centerline and then executed a left turn toward Runway 35R. Shortly after the airplane turned toward Runway 35R, ATC observed the airplanes landing lights point straight down, and the airplane then disappeared from the controllers view.