It's nighttime at Eureeka's castle, and Eureeka decides to go to bed. Meanwhile, Magellan and Batly are having a stay-awake contest, which they want Eureeka to join, but she is too sleepy to do so.
After hearing one of Batly's scary stories, Magellan sees a monster outside the castle wreaking havoc, and it's up to Eureeka and the gang to stop him.