and got him at gunpoint, arrested him. >> reporter: wow. at -- at gunpoint? >> yeah. i wanted him to know he -- that it was real serious on my part and not to play anymore. >> reporter: the investigator interrogated derek for more than two hours. >> you know just take a deep breath and be honest. >> reporter: he quickly admitted he had an issue with pain 00 on medication. >> so i'm addicted to -- uh -- to the vicodin and soma. >> reporter: and came clean about all his names. >> obviously my name then um -- allred, a-l-l-r-e-d. aldrich. >> how do you spell that? >> uh -- a-l-d-r-i-c-h. >> what other first names would you have used? >> usually always derek. i mean -- >> okay. any richards? >> uh -- i think i have in the past, yeah. >> reporter: but when the investigator asked him about getting drugs for free, well, the con man wasn't about to confess to that. >> you can go into a hospital, impersonating a firefighter, right, and then how would you use that to get pills? how would a person do that? >> i don't know to be honest with you. >> have you ever done that?