. >> rick zender was mandy stavik's boyfriend.s, they wanted to question him. >> we dated for about three years. we've probably broken up two or three times. it's just one of those high school things. >> that point in the relationship it was on and off, on and off, but he had brought her home from college. >> they checked to see where her ex-boyfriend was. >> i want to be viewed as a suspect. that's what they should do. that's their job. usually, it's the person closest that's the killer. >> they spoke to him. he was extremely forthcoming. he came in and gave a statement. >> the authorities ultimately cleared rick zender, but of course they had to look at him. >> the first night, didn't hear anything. so by the second day, it was pretty obvious that this was even more serious than we originally thought. >> it was such a mystery. i mean, beautiful 18-year-old smart, strong women don't just vanish. they don't do that. >> we're checking a lot of side roads and found something they thought was a little bit suspicious. >> the first thi