an hbo documentary on the case. >> i tried to watch it. i made it part of the way through the first one, and it was literally like being there in the courtroom again. and it's too much. it was an overload. >> reporter: but in new york city, a young woman couldn't keep her eyes off the screen. lori davis wrote a letter to echols in 1996, and a love affair quickly blossomed. three years after davis' first letter, she and echols were married in arkansas's tucker maximum security unit. but their story of love behind bars is not unique. even the most notorious convicted killers have attracted outside admirers and relationships often blossom across the prison walls. >> i think many of the women who are seeking out prisoners, even without their own knowledge are looking for someone who can't actually commit to an ongoing relationship. they find it thrilling, and at the same time, it's safe, right, because he is behind bars.