>> that there were pills involved. >> it was a long frustrating, 15 month investigation. but rick was finally close to the answers that he had promised erica's grandmother. >> what up to going some of those times where you might have felt like you are hitting a dozen? >> two year old baby, erica hughes >> five days later after interviewing -- detective ronald was ready to bring in quisenberry for some tough questions actually, he had enough questions to arrest him earlier, but he wasn't ready yet he wanted more. both men from the walgreens video, so he could play them off of each other in dueling interrogations. and now he had them. >> you've been waiting and waiting patiently so it's time to do your thing, right? >> now it's time. >> the detective moves to get each suspect to implicate the other. not knowing he was nearly out of time. >> coming up,. >> so you didn't know you are playing beat the clock? >> no, no idea. >> when dateline continues. when