One of the last phone calls William "Billy" Smolinski made before disappearing in Connecticut back in August 2004 was to a man who was also romantically involved with a woman Billy had been dating.Billy left a voicemail telling the man to "watch his back."Police believe Billy was murdered, but by whom? And where is his body?Billy's heartbroken parents have been trying to find him for two decades.Eyewitness News investigative reporter Kristin Thorne steps in to help.Learn more about your ad choices. Visit megaphone.fm/adchoices