Cam Jansen

Cam Jansen and the Ghostly Mystery by David A. Adler, 1996.

Cam Jansen’s Aunt Molly takes her and her friend Eric to buy tickets for a Triceratops Pops concert.  Triceratops Pops is a singing group that dresses up like dinosaurs, and many of the fans buying tickets also wear dinosaur costumes.  While they’re standing in line, someone dressed as a ghost starts sneaking up behind people and scaring them by yelling, “Boo!”  At first, it seems like a mildly annoying prank, but then one old man standing nearby seems to have a heart attack when he is startled.

The guards standing near the ticket booth rush to help the man and call for an ambulance for him.  However, while they are distracted, the person in the ghost costume robs the woman selling tickets, taking all the ticket money and her own money from her purse.

Cam is convinced that the old man who collapsed was part of the thief’s plan and that his “heart attack” was just an act to distract the guards.  She noticed that he seemed to be wearing a wig to make himself look older.  But, there are two other clues that are important: the magazines that the man dropped when he fainted, and the fact that the ghost costume was found in the ladies’ restroom.  Once again, Cam helps the police with her amazing memory!

The book is currently available online through Internet Archive.