The Capture of Cerberus - The 12th Labor of Hercules

His 12th and 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 knew how much Hades loved that fierce, bad tempered dog. Hercules asked Hades' permission to briefly capture Cerberus, and told him why. Hades agreed that Hercules could try, as long as he used no weapons and did not hurt poor Cerberus.
Hercules used his bare hands. He scooped all three heads up at once, and strangled Cerberus until he was unconscious. He gently carried the dog off to King Eury's. Cerberus began to regain consciousness as Hercules approached the king. The king scurried behind his royal throne.
Hercules explained he had to get the dog home right away. King Eury stuck his head out from behind his throne and quickly agreed that Hercules should leave immediately. Hercules promised to be right back.
After Hercules delivered Cerberus safely home, Hercules quickly returned to the palace, eager to be granted immortality. But Hera was nowhere to be found. Neither was King Eury.
It was Zeus who granted Hercules immortality. Zeus proudly brought his son Hercules up to the heavens.