Now You See Him, Now You Don't (Two Of A Kind, Book 21) by Mary-Kate Olsen
Meet Mary-Kate and Ashley, the Tween Queen Twins! Your new best friends have just arrived...
Mary-Kate and Ashley have great tricks ready for the Harrington Magic Show. They're sure to be a hit! But before show time, Ashley's partner leaves her trapped in a box and Mary-Kate's mind-reading horse disappears. The girls are going to need some real magic to get out of this one!
By Megan Stine.
From the series created by Robert Griffard and Howard Adler.