she had the motivation to want this to happen. >> when "dateline" continues. >> melissa oxley was just 27 years old and already a widow. her 36-year-old husband, ben, shot dead while he slept in bed right next to her. as far as she could tell, said melissa, the shooter managed to break into the house, walk right into the master bedroom, shoot ben without harming her and leave not a trace of evidence behind. the case boggled the detective's mind. >> is there somebody who doesn't like him? is it a murder for hire pay? what could this be? >> melissa's closest friend believed her when she insisted she had nothing to do with it, in fact, she lost the love of her life. and that now she and those around her were probably in terrible danger. >> because you don't know who did it. you don't know if they're going to come back for melissa. melissa was supposed to be in that. >> melissa meanwhile tried to be a source of comfort for her 6-year-old stepdaughter alyssa. the little girl's father had been her world, leaving her now in a world of chaos. and with her home and love nest now a crime scene,