"Mr. and Mrs. Watson and their porcine wonder, Mercy, are off to the Bijou Drive-In. What will happen when the Lincoln Sisters, Frank, Stella, and a gaggle of familiar characters get the same idea for a night out? With the tempting scent of hot buttered popcorn wafting through the air, everyone's favorite pig leads the way in this hilarious romp featuring movies, mayhem, and Mercy!" -- p. [4] of cover.

Henry, Jessie, Violet, and Benny have never been to a drive-in movie theater before, but they're visiting a friend who owns one. The children love to eat popcorn in the car and watch movies under the stars. But strange pranks are disrupting the fun. One night the sound system starts playing loud music during the movie, and a couple of the theater employees seem to be hiding a secret. Then, late at night, a ghost is seen walking around the empty grounds...