He found a hidden entrance to get under the neighbor's deck next door and was hiding there for 4 days. We left his litter box and food/water and items of my clothing outside. We left the door open for him to come in and I saw him by the door last night. He ran back under the deck and wouldn't come out, but by morning he was sleeping on his favorite cat tree. Tired and hungry, but otherwise clean and unscathed. Thanks to all who went out of their way to help us and give us advice. We really appreciate it and could not be happier that we have our Rocky back!