was patrick anthony russo that guy? maybe. maybe not. rs away when they knocked on his door. the man who woke up to answer it looked like the sketch. coming up, patrick russo seemed an unlikely killer. >> i got my ged. i went to college. i studied for theology to become a minister. >> odd coincidence, he was in diane's area the day she was killed. >> do you remember ever talking to her? >> when dateline continues. >> when dateline continues you look amazing. and you look amazingly comfortable. when your v-neck looks more like a u-neck... that's when you know, it's half-washed. try downy fabric conditioner. unlike detergent alone, downy helps prevent stretching by conditioning and smoothing fibers, so clothes look newer, longer. downy and it's done. ♪ here? nah. ♪ here? nope. ♪ here. ♪ when the middle of nowhere... is somewhere. the all-new chevy trailblazer. ♪ >> tips led detectives to the doorstep of patrick russo, a man matching the description of the mysterious stranger seen in diane holi k's neighborhood the day of the murder. >> we s