The lovely mortal woman Alcmene, a descendant of the hero Perseus, unknowingly catches the eye of everybody's favorite dirty-old-god – Zeus, king of the gods.
One night, Zeus disguises himself as Alcmene's husband, Amphytrion, and sleeps with the pretty lady. She becomes pregnant with Heracles.
That same night, Amphytrion comes home and also gets romantic with his wife. She conceives another baby boy named Iphicles. (Didn't she wonder why her husband showed up twice?)
Hera, Zeus' wife, is none too pleased that her cheating husband is up to his old tricks again.
Just before it is time for Heracles and Iphicles to be born, Hera makes Zeus swear that the next descendant of Perseus to be born will be high king. Zeus thinks this baby is going to be Heracles and agrees without any argument.
Hera, of course, has some tricks up her sleeve.
Determined to rob Heracles of his birthright, she enlists the help of Ilithyia, goddess of childbirth. Ilithyia simultaneously speeds up the birth of another descendant of Perseus named Eurystheus and slows down the birth of Heracles and Iphicles by sitting cross-legged and tying her clothes into knots.
Heracles and his half brother probably would have never been born if it weren't for the help of Galanthis, a servant and friend to Alcmene.
Sneaky Galanthis fools Ilithyia by telling the goddess that Heracles has already been born. This startles Ilithyia and distracts her long enough for Heracles and Iphicles to be born.
Unfortunately, though, Eurystheus beats his cousin into the world, and Heracles doesn't get to be high king.
Alcmene is so afraid of Hera's wrath that she abandons baby Heracles.
Fortunately for our little hero, however, Athena, comes along and saves him.
Athena decides to play a little trick on Hera and takes baby Heracles to the queen of the gods to be breastfed. Hera, not knowing who the baby is, agrees, but Heracles either sucks too hard or bites her nipple (depending on who you talk to). As Hera yanks her breast away, her milk sprays into the sky and creates the Milky Way.
Ironically, little Heracles, whom Hera hates, is made extra strong by her breast milk.
After this, Athena takes Heracles back to Alcmene and tells her to take better care of the little tike.
Hera is now raging mad and decides to send two big snakes to eat Heracles in his cradle. To Heracles, however, the snakes are just fun toys, and he squeezes and squeezes them until they're dead.
Everybody around is amazed at how strong a baby he is.
It's at this point, that Heracles actually earns the name we know him by. (Alcmene and Amphytrion first named him Alcaeus.) Since part of the reason he's so super strong is because of Hera's steroid filled breast milk, everybody around starts calling him Heracles, which basically means glory by the aid of Hera.