(From the publisher):
Zoinks! The Scooby Gang needs you! Join them at a live enactment of a real medieval tournament. But, Beware! A ghost knight has come back to enforce an ancient curse. He's after anyone who dares to wear the fabled crown of King Arthur. Uh-oh! Someone has just put on the crown! And here comes trouble! How will Scooby and the gang get out of this one? How will you? Think fast because this is one Knight you'll never forget.
Original title: The Case of the Purple Knight
Genre: Fiction→ Children & Young Adult→ Mystery
Fiction→ Children & Young Adult→ Adventure