COULD A "MR. RIGHT" ON MATCH.COM BE A SERIAL DATE RAPIST?, ON "PRIMETIME: CRIME," WEDNESDAY, JULY 15 ON ABC

Those who date online might expect a certain amount of innocent fudging in others' profiles. There's always the risk of encountering a liar whose online self-description is far from the real person. But police say when Jeffrey Marsalis created his Match.com profile, his intentions were far less innocent than getting a date. Many of the women who dated him say he wasn't just a conman. In fact cops and criminal prosecutors say he may have been the worst date-rapist in the nation's history. David Muir investigates the man who called himself "Dr. Jeff" and how he was able to lure so many women. Muir sits down for an exclusive interview with Marsalis himself, who breaks his silence on "Primetime: Crime," WEDNESDAY, JULY 15 (10:00-11:00 p.m., ET) on the ABC Television Network.

Police say Marsalis used an impressive and fabricated online profile to meet women whom he would take out, drug and rape. His profile on Match.com said he was a trauma surgeon. At other times he told women he was a CIA agent and even an astronaut. And his lying worked. He won over dozens of educated, professional women, ranging from a lawyer to a researcher to a marketing executive. But eventually 21 women in Philadelphia would press charges against him. Muir sits down with four of those women to hear their side of the story. Several women have a similar story, that they felt something was wrong and that perhaps something even criminal had happened in "Dr. Jeff's" apartment, but they say he was able to convince them that everything was fine. He was so convincing that initially none of the women went to police. In fact, many of them willingly saw "Dr. Jeff" again.

After two separate trials, two separate juries acquitted Marsalis of rape charges. Jurors were convinced that the women were simply angry they had been duped by a smooth talker. But the hour reveals that accusations from another woman across the country in Sun Valley, Idaho sparked a third trial this past spring that turned the case upside down. "Primetime" is there with the verdict and to hear from Marsalis himself.

David Sloan is the executive producer of "Primetime: Crime."