Hercules and the All Nighter

Hercules and the All Nighter is an episode of Hercules: The Animated Series. It aired on October 21, 1998.

Summary
Hercules and Icarus didn't study for their finals, so they go to Morpheus (Jonathan Katz), god of sleep, on Cassandra's joking suggestion, to ask if he will take a week off; he refuses, but Hercules accidentally puts his sleep blanket over him, causing Morpheus to sleep and hence causing no sleep in the world. Hercules and Icarus use this time to study, despite that at school and elsewhere, odd things are happening – Phil keeping odd hours and Cassandra acting cheerful. Hades, as a result of all the accidents, now has an overflowing influx of dead people, and intends to keep it that way, so he has Pain and Panic watch Morpheus. However, when Hercules discovers that the rooster Alectryon (Steve Hytner), a former hero who Morpheus caused to fall asleep on guard duty, can crow to wake him up, the duo set out to find the rooster. Hercules confronts Morpheus just as dawn approaches, after Hades unsuccessfully tries to barter with Alectryon, who crows and wakes the god. As punishment, Hades is forced to give up the souls that died (because they died only due to lack of sleep) while Hercules and Icarus must fly across the night spreading sleep.