the devotion to gaudiii runs deep here. japanese sculptor etsuro sotoo has spent 35 years in this church, and this is where he expects to be for the rest of his life, sculpting the figures that adorn gaudiii's final masterpiece, consumed by the man and his vision. >> etsuro sotoo ( translated ): gaudiii teaches me and helps me solve problems in my work. for me, he's not dead. >> logan: why did you convert to catholicism? you became a catholic. >> etsuro sotoo ( translated ): i was a buddhist, but after working here, i realized i knowing gaudiii. and to know him, you have to be in the place he was, and that was a world of faith. >> logan: gaudiii's deep faith is the reason he became known as "god's architect." this is one of the few photographs ever taken of him. he was 31 when he started working on the sagrada famiiilia. and over the next 43 years, it became an obsession. >> van hensbergen: he looked like a homeless person. his trousers were held up with string. his clothes were kind of frayed, and... because all he was int