. ♪ >> the wabash valley correctional facility in indiana houses a large number of inmates who are, ore considered, mentally ill at the time of their crimes. when "lockup" visited there, we met two such inmates. they killed after their own minds turned on them. and their murders took on dimensions that were not only shocking, they were unimaginable. >> i'm frank street jr., i'm 38 years old. i've been down since 1993 for shooting my mom. >> during our first day of shooting at wabash, our "lockup" crew met frank street, an inmate housed in the prison's residential treatment unit. at the time of the interview, street was experiencing involuntary tremors due to his medication. >> i started having delusions that the people were out there hurting me. and i have this video cassette tape of a party showing people hurting me. and i showed my parents. they said no, no, there ain't nothing to that. i said well you guys are crazy. i'm watching it. they was thinking sane, i was the crazy one. >> a short time later street's delusions got the better of him. >> i load up the 30-30 because i thought p