half-hour between -- 20 minutes between when they tied us up and when they actually headed into the galleries to start doing it. i've seen a lot of people questioning, what were they doing? they were probably wait the to see if i did press the panic button. they were probably waiting to see if the cops were going to show up. >> reporter: according to the in fbi, nearly 9 of every 10 museum heists have an inside component. rick abath who let the thieves in was interrogated for days. he also took lie detector tests. he was never charged with anything. and when we talked to him, he maintained he had nothing to do with the heist. and what about the regular night watchman who called in sick that night? rick remembers after he buzzed the thieves in to the museum, they asked him if he was alone. >> i wonder if that -- are you here alone? because there were provisions for are a single guard to be