Hercules and the Grim Avenger

Hercules and the Grim Avenger is an episode of Hercules: The Animated Series. It aired on February 22, 1999.

Summary
After the Minotaur wrecks several temples in Athens, Hercules teams up with the Grim Avenger, a superhero who narrates his every move and is really Theseus (Eric Stoltz), a visiting prince who likes Cassandra (and who Adonis and Icarus mutually hate) to stop the beast. Theseus holds a party at the temple of Aphrodite to lure the Minotaur, and Hercules discover his double identity. The trick works, but Icarus is injured in the process; Theseus, as the Avenger, tells Cassandra he wants her to look after him. Meanwhile, Hercules tracks the Minotaur to an alley of temples, and uncontrollably angry, the two fight, destroying temples in the process. Theseus convinces Hercules not to kill the Minotaur and be himself, so Hercules turns him in to Zeus. The Minotaur is put back in the Labyrinth and Theseus, heading home, signs Icarus' cast.