Attack of the Graveyard Ghouls is the eleventh book in the Goosebumps Series 2000 book series.
 
hen Spencer Kassimir knocks over the headstone, the zombie-like ghoulish figure of Oswald Manse was back from the dead where he ends up pushing Spencer out of his body and possesses it, leaving Spencer in the spirit world with other souls who tell Spencer about how evil Oswald and Martin Manse were when they were living. Spencer tries to get back home and confront Oswald by possessing several bodies. After failing to convince him, Spencer seeks Audra's help. But there, it is revealed that Audra's body was already possessed by Martin when they first visited the grave. After finding Audra, she and Spencer try to stop the two ghoulish brothers. After doing a special ghoul dance, Martin and Oswald die and Audra and Spencer get their bodies back. However they end up in each other's bodies.