Oh My Goddess is the fifth Charmed episode to feature characters drawn from Greek mythology, following Hell Hath No Fury, featuring the Furies (S04E03) and Muse to My Ears, featuring the Muses (S04E09), Siren Song (S05E04), featuring a Siren, and Nymphs Just Wanna Have Fun (S05E19) featuring a satyr and nymphs. The double episode, which ends season five, includes three Titans as characters, one of which is named Cronus, and also has the three Charmed Ones turned into goddesses of Love, War and Nature, loosely based on ancient Greek goddesses.
Part 1
A demon uses a spell to awaken two Titans, the male Demetrius and the female Meta, who have been entombed in ice. They wear short white robes, marking them out as ancient Greek. The demon wants to use their powers, but they kill him, and then find and awaken the third Titan, Cronus, whose power they need to obtain revenge against the Elders, who were their original captors. Meta goes after white lighters (guardian angels) in order to take their power to "orb" or transport, and she does this by turning them to stone when they look into her eyes (like the Gorgon Medusa).
San Francisco is suffering from a heatwave, and witch and white lighter Paige is having unusual dreams about "ancient wars and weird magic." She predicts earthquakes, with a supernatural cause, and takes her sister Phoebe to the now empty ice tombs which are the source of the evil she can sense. The third sister, Piper, is at a children’s birthday party, when her husband, Leo, a white lighter, is called away to the temple of the Elders above the earth, because a white lighter has gone missing. He misses marriage guidance counselling with Piper, much to his wife’s annoyance, and is called back to the Elders again, where he suggests that the white lighters should stop orbing so that they cannot be easily found.
Paige finds reference to the Titans in the Book of Shadows, the Halliwell family book which includes information about the supernatural world. She reads that the Titans were "ancient gods who were entombed because it was the only way to stop them." She orbs to attract a Titan, so that she can destroy the Titan using a vanquishing potion, but when Meta appears the potion has no effect and Paige is turned to stone. Chris, a white lighter from the future, appears and saves Phoebe. He explains that many statues in museums and universities are actually people turned to stone. When Meta returns to Cronus and Demetrius she is killed by Cronus for her "incompetence" at bringing a third white lighter to them, and Cronus and Demetrius take the orbing powers from the two other white lighters Meta had turned to stone.
Supernatural creatures, including nymphs, elves, leprechauns and fairies, turn up at the Halliwell household looking for protection. Chris explains that the witches cannot destroy the Titans. He tells Piper that the Titans were vanquished before by mortals who were given "a hell of a lot of power" by the Elders, but this power "went to their heads" and "they declared themselves gods and forced the world to worship them". Piper realises that "The Greek gods, Zeus, Athena, Aphrodite" were actually mortals.
Piper sends Leo to warn the Elders that the Titans will be using the orbing powers to reach their temple and kill them, but when he gets there most of the Elders are dead, and some have fled. Chris encourages Leo to give the witches the powers of the gods. He opens an urn in the temple of the Elders and white light comes out. This surrounds the three sisters, and when it disappears they are each wearing a long white dress, Paige has a trident and Phoebe has long blonde hair. Chris tells them that they are gods.
Part 2
Piper is incredulous saying that they look as if they were going to a "costume party" but Chris assures them that their clothes represent their position and power. Paige is the goddess of war, Phoebe is the goddess of love, and Piper has "dominion over the earth and all its natural elements." She is needed to bring balance to the other two. Phoebe goes to the charity event she was organising, with a bachelor auction, and all the bachelors want to bid for her. Paige defeats demons who become her army. Piper finds Paige and sends the demons away with an earthquake, then finds Phoebe at home on the sofa surrounded by topless men, fanning her with ostrich feather fans, feeding her grapes and massaging her feet. Piper sends them away with a gust of wind. She calls for a "morality check", reminding them that the Greek mortals abused their powers. Chris says they became "petty, evil, vindictive."
The Titans have tracked down a remaining Elder, and he is saved by the witches but they cannot destroy the Titans. The Elders are together in a safe house, organised by Leo. At home, Phoebe tries to lure Demetrius to her, seducing him, but Cronus stops this and they disappear. Paige reads that Cronus ate his own children, although Chris says this is a fable the witches cannot come up with a workable plan to defeat him. Eventually Leo comes to help them. He tells Paige she needs to focus, and she comes up with the solution; they need to "declare themselves gods." Leo explains that he has chosen them as they will not abuse their powers.
The Titans come to the house looking for Leo, who has become an Elder, much to the distress of Piper, as he will be unable to stay with her, as Elders do not live on earth or have families. Piper is unharmed by the Titan’s lightning bolts, and she causes the room to shake, then a hole is created and the Titans fall through it, then the hole seals itself. Leo then asks the Charmed Ones to give back there powers as the Titans have been defeated, but Piper disappears. Paige and Phoebe give back their powers, returning them to the urn. Meanwhile, Piper is causing a massive storm from the top of a mountain, brought about by her emotional turmoil over the loss of Leo as her husband. Her sisters go to Piper, reminding her that she needs to take care of her son. She goes to the Elders’ temple and confronts Leo, eventually giving back her powers. Leo takes her pain away, and she returns home, appearing to have accepted that Leo is an Elder. Chris becomes the Charmed Ones’ new white lighter.
