Ghost Town at Sundown

Osborne, Mary Pope (1997). Ghost Town at Sundown. New York, New York: Random House.
In this Magic Tree House book, Jack and Annie follow a rabbit that leads them to their tree house and Morgan. The book that the librarian gives them is a book about the wild west. Jack and Annie travel back into time right into the middle of a ghost town. As they are talking, a band of horse rustlers comes through town. Jack and Annie hear that they are leaving a colt behind because he is slowing them down. Jack and Annie decide that they need to reunite the colt with his mother. As they are heading out to do just that, the horses' rightful owner shows up. Together the three of them take back the mustangs and make it to safety. In the process Jack and Annie solve their riddle and encourage Slim, the cowboy to stop capturing wild mustangs and become an author. That being accomplished, the two get back to the magic tree house and return home.
The pacing of the books in this series is very quick. This is good for young readers so they do not get bogged down and lose interest in the book. The mood in these books shift. There is always some "scary" moments for the characters. These are balanced with more lighthearted times.