Alan Chenkin, Learned about celebrities reading magazines at the supermarket checkout
I would offer him a glass of water, some sympathy, and directions, as I would any lost traveler at my door. I always try to be a gracious host.
It is highly unlikely he would show up in costume (although that makes for an amusing story). In fact, it is highly unlikely – a member of his entourage might stop in. (Grey Poupon moment?)
Why Johnny Depp may be disoriented or confused? – Johnny Debt, sorry, Johnny Depp has spent all of his $650 million in lifetime earnings – My9NJ
Johnny Depp Bio: OMG! Look What Johnny Depp Has Done Now. – Johnny Depp Web
Johnny Depp – IMDB profile
Johnny Depp, posters and autographed items From Amazon
Let me ask you –
What if you showed up at his house?
Edited from my answer on Quora.