Hercules did 12 labors, each one seeming impossible to accomplish. The final labor was to descend into the underworld, and bring back Cerberus, the three-headed dog who guarded the gate to underworld, home of the powerful god, Hades. Hercules asked Hades' permission to briefly capture Cerberus and told him why. Hades agreed that Hercules could try, if he used no weapons and did not hurt poor Cerberus.
Hercules went to a place called Taenarum in Laconia. Through a deep, rocky cave, Hercules made his way down to the Underworld. He encountered monsters, heroes, and ghosts as he made his way through Hades. He even engaged in a wrestling contest!
There's the cave! Time to find Cerberus of the Underworld
Near the gates of Acheron, one of the five rivers of the Underworld, Hercules encountered Cerberus. Undaunted, the hero threw his strong arms around the beast, perhaps grasping all three heads at once, and wrestled Cerberus into submission.
The monster soon grew weary, and having run out of breath by the strongman's chokehold, finally yielded to Hercules. Cerberus is one of the few monsters who ever met Hercules and survived. Unlike other monsters that crossed his path, Cerberus was returned safely to Hades, where he resumed guarding the gateway to the Underworld. THE END