she said okay. so we left. reporter: cheryl took her daughter to this nearby ramada inn. she never heard from joe again. the next morning this is what cheryl drove up to. the morning of the fire, they took refuge at a neighbor s home. it would be there that she would discover the fate of her husband on the local news. they interrupted the house fire to show that a plane had crashed into a building. reporter: how did you react when you realized it was his plane and it was him? well, i don t think i did react. i think i was just just in complete and utter shock.
what s your direction of flight, sir? reporter: at 9:44 a.m., joe stack was headed for his final flight. joe stack knew exactly where he was going, the echelon building in austin, which housed the irs. it was like a fireball. people let out a scream all around you. people were crying. reporter: stack slammed his plane between the first and second floors of the building. it exploded on impact. one man in the building was killed, vernon hunter, an irs employee. immediately, there were fears that this was an act of terrorism. but it wasn t. it was simply one man s grudge against the irs. and then came the manifesto. before stack would die by suicide, the 53-year-old software engineer would leave behind a rambling diatribe online, where he railed against
ready for departure. reporter: and was cleared for takeoff. 39 delta, cleared for takeoff. what s your direction of flight, sir? reporter: at 9:44 a.m., joe stack was headed for his final flight. joe stack knew exactly where he was going, the echelon building in austin, which housed the irs. it was like a fireball. people let out a scream all around you. people were crying. reporter: stack slammed his plane between the first and second floors of the building. it exploded on impact. one man in the building was killed, vernon hunter, an irs employee. immediately, there were fears that this was an act of terrorism. but it wasn t. it was simply one man s grudge against the irs.
that he was violent. how could i possibly know he would do a thing like that? cheryl met joe stack through a mutual friend in 2005. both loved music. cheryl played piano, joe played bass guitar. two years later, in a small ceremony in austin, they married. joining them was cheryl s 12-year-old daughter, margo. did he ever talk about how he was angry with the government, angry with the irs? when we were dating, he did talk about the irs. he didn t seem so angry. he just didn t like them. reporter: but actually, joe s emotions ran much deeper. in the 80s while living in california, he was part of an anti-tax movement, even forming his own tax exempt home church. his run-ins with the irs continued for decades.
i don t know who that is. i don t know that man. i learned a lot being up in the air with joe. one of the things i learned up there is that the sun is always shining on the other side of the clouds. it might be a really dark day. it might be a terrible, terrible day, but on the other side of those clouds, the sun is shining. reporter: coming up he never gave any idea that he was involved in murdering people or eating them or whatever. reporter: randi kaye on a sadistic serial killer and a father s anguish. he was ordered by the court to undergo counseling. i visited the psychologist. she knew something was wrong but