. >> wertheim: one name that keeps coming up is massimo de caro. familiar name to you guys? yes, massimo de caro was prosecuted by the italian authorities for pilfering thousands of rare books and he was involved in the sale of at least one of the columbus letters at issue. >> wertheim: this was someone who's been involved in these kind of crimes before? >> mccall: yes, correct. >> wertheim: fair to characterize him as a person of interest? >> mccall: he is a subject in the investigation. >> wertheim: the columbus letters themselves may be hard to track down, but this subject in the investigation is not exactly in hiding. massimo de caro, a notorious italian book thief, just finished serving a seven-year sentence for stealing thousands of ancient books and manuscripts from italian libraries, and selling them overseas. to our surprise, he agreed to meet with us at his home in orvieto, a hill town an hour's drive north of rome. to say that he professes his innocence would be an act of considerable understatement. the police say you are a subject in this investigation. does tha