Right after Cordelia has her vision, Wesley goes to the whiteboard. In the "Case" column he writes "N.D.U.O." underneath what looks like "CARYNSS" crossed out. But once they find out that it is a Prio Motu demon and Angel writes it on the whiteboard, "N.D.U.O." disappears even though Angel did not rub it off.
In the opening credits there is a shot of a girl standing alone on the corner of a street. This was taken from the Buffy episode "Anne", when Buffy was staying in Los Angeles.