there is the klaas phobia, mental breakdowns and those blood curdling screams. reporting from the front line of an american nightmare, abc's dan harris spends 48 hours in solitary confinement. >> announcer: from the global resources of abc news, with terry moran, cynthia mcfadden and bill weir in new york city, this is a special edition of "nightline," no way out. september 20th, 2012. >> good evening, i'm bill weir. well, tonight, across this country, some 80,000 prisoners are locked in solitary confinement. prison reformers pushed it as a humane alternative to hanging, almost 200 years ago. but some modern reformers think it is pure torture. practice has led to congressional hearings, u.n. reports, inmate hunger strikes. to better understand the toll of forced solitude, abc's dan harris volunteered to spend 48 hours in the hole. >> reporter: i'm cuffed and stuffed in the back of a sheriff's vehicle. >> right in front of you. turn around, put your hands -- >> reporter: this is everybody's worst nightmare. >> come on this way, please. >> reporter: the further we