leah frazier: i'm like, the weight machine? she doesn't lift weights. andrea canning: a home gym mysteriously turned deathtrap. a husband suddenly turns suspect. hello, and welcome to "dateline." it's the case of a fit, young woman who died suddenly. her friends and family were told it was a freak accident in a gym, the kind of thing that could happen to anyone. equipment does, at times, malfunction, but so do relationships. here is dennis murphy with the beauty and the beast mystery. dennis murphy: the images are fuzzy on that old home video of the wedding reception, but anyone who was there remembers the event vividly. the bride all in white, and the groom? he's the dance partner in the goofy beast costume. kind of a strange way to begin a marriage, some guests murmured. beauty and the beast. but then, it was a union that would end strangely, a last dance still more than 10 years away at that point. lisa the bride, of course, had no idea what was in store for the two of them. she glided about with her signature 50,000 watt smile. you can't fake a smil