Dionysus sets the stage for tragedy when he determines to punish the house of Cadmus for denying his godliness. He takes over the minds of the women of Thebes, driving them to dance around in the mountains, worshiping him. This causes King Pentheus to lash out against the god. It's clear, as the two sides square off against each other, that some serious craziness is about to go down.
At first Dionysus's retaliation against the house of Cadmus seems pretty harmless. All the women are out dancing in the woods. Cadmus and Tiresias put on some fawn skins and do some dancing of their own. Overall, the play has a light and playful feel. This, however will not last.
When the obstinate King Pentheus starts to crack down on the Dionysian uprising, things start to get ugly. Some of his men disturb the Maenads' woodland revelries and the ladies go crazy, ravaging the countryside. When Pentheus arrests Dionysus, who is in disguise as a mortal, things start to get really raw. Dionysus summons earthquake and lightning to destroy his jail and lacerate the palace.
Nightmarish doesn't even describe it. Dionysus convinces Pentheus to go spy on the Maenads, telling the King that he'll be safe if he's disguised in women's clothes. Then the god betrays the King and points him out to his followers. Pentheus ends up being ripped apart by his own mother, Agave, on of the Maenads. The rest of the crazed women finish the job, tearing at his flesh and throwing it in the air.
Maddened Agave returns to Thebes, clutching the bloody head of her son, under the false impression that it is the head of a lion. The audience is moved to fear and pity as they watch her slowly realize the terrible thing she's done. Dionysus appears in all his godly glory and punishes Cadmus and Agave. The Bacchae, is different from a lot of tragedies in that it doesn't tell the story of a tragic hero's downfall. We don't find our hero, Dionysus, suffering and bemoaning his fate at the end of the play. Instead, it's everybody else that suffers.