He was the football player, she was the homecoming queen. They fell in love, got married, had four beautiful daughters and became prominent members of their church community. But when she started to feel ignored at home, her eyes wandered a few pews back to the church youth pastor -- her husband's best friend. A month later, the husband was found stabbed to death and the trail of evidence would lead back to the lovers. Dennis Murphy reports Dateline NBC Friday, 9pm/8c.