Dave always gets excited when he has a visitor. He is especially excited when there is an unexpected visitor, which is most of the time, because he is a cat and doesn't get to invite his own visitors over. Here you can see Dave one day when a plumber was visiting. In this case, Dave found the visitor to be somewhat suspicious, so Dave put his investigator hat on. After the plumber left, Dave stared intently at the doorknob for quite a while. Like any good investigator, Dave knows the importance of patience in any investigation.