Escape from Plot Mountain

You and your friends planned to spend the afternoon hiking up to the highest point of Plot Mountain, known for its spectacular views, but the weather has changed suddenly. Temperatures are dropping and fog is rolling in, making it difficult to see what's ahead of you. To make things worse, you've been using the GPS on your phone to find your way and the battery just died. You stumble across a ranger's cabin, which you are sure must have a map inside, but the door has a series of locks on it. You and your friends must crack the codes to get inside, find a map, and make your way back down Plot Mountain to safety.