Season 01, Episode 17:
That 70's Episode
At the manor Prue and Phoebe are looking through photos. Phoebe states that there aren't any photos of her, only of Piper, Prue, Victor, Patty and Penny. However, Prue is able to find two pictures, one of her with Patty and another with Penny. Piper rushes in asking for a paper and pen, she goes to open a drawer but can't. Phoebe thumps it twice with her fist and once with her foot, and it opens.
The doorbell rings and they all leave to answer it; Piper notes that Gram's friend comes every year, same day and time, which she believes is an admirer of Grams. Every year, he brings flowers and "accidentally" drops them on the floor. He does so again, but this time Piper freezes the vase and grabs hold of it. The scene unfreezes, the man immediately states that the clock only chimed five times, however, it's noon. The man explains he knows they froze him and they now have their powers. Piper denies it and it turns out the warlock is named Nicholas. He then proceeds to put on a red ring and his appearances changes from an old man to a youthful appearance.
He explains that 24 years ago, in order to save her life, made a pact with him to give him their future powers. Piper tries to freeze him, but it is revealed that the ring grants him immunity from their powers in order for him to kill them and take their powers. Prue denies it, Piper and her then attempt to use her powers on him, to no avail. He uses his power to burn the sisters up from within, but Phoebe kicks him down and the sisters take the opportunity and run to the attic. They begin to look through the book of shadows, Phoebe finds a spell in the Book of Shadows to unbind a bond. She says the spell, orbs of light begin to surround them and the sisters disappear.
They reappear, still in the attic, and the phone rings — with an old-style copper bell. They go open the door and wonder who's phone it is, they hear someone speaking and debate who will check. Piper and Phoebe decide to have Prue see who it is. Prue peeks down and finds Grams talking on the phone, and a very young Prue and Piper running in the house. Prue returns to the attic and reveals to Piper and Phoebe that she was themselves.
They realize they've gone back in time. In the attic, the sisters contemplate what happened. Phoebe states that there is nothing in the Book of Shadows that can help them. They decide to leave the house unnoticed. As they sneak out the see Grams is talking to Patty on the phone. The sisters eavesdrop through an extension and Patty has had a premonition of three female warlocks in the manor, with one of them is holding little Prue. Grams finds it hard to believe; Patty only has the power to freeze time. The sisters continue to try and sneak out, as they go downstairs. Grams calls little Prue and Piper who are racing through the living room.Little Prue squints her eyes and to the adult sisters' surprise, a couch moves in front of the doorway just before little Piper gets through it. Little Piper cries foul at little Prue for using magic. The adult sisters are surprised; they don't remember having powers that young. Prue and Piper befriend their younger counterparts. Just as they are talking, Grams walks in. Before Prue has a chance to explain, Grams exclaims, "Warlocks, be gone!" waves her hands and violently blows the adult sisters out of the manor.
As the sisters runaway from the manor, Phoebe finds a newspaper and the date is March 24, 1975. Phoebe realizes that Patty is newly pregnant. The sisters track Patty to her job at a diner. Phoebe stays outside, lest Patty mistake them for the warlocks. Also, since she only has a passive power, she can't prove that she really is Patty's daughter. In the diner, "Gypsies, Tramps and Thieves" plays, Patty comes to Piper and Prue's table. Patty seems to recognize them. Piper and Prue find that their powers don't work—presumably because little Prue and little Piper have powers in this time. A co-worker calls Patty stating to have a call for her. They inform Patty that she is pregnant, but she declares that to be medically impossible.
Grams calls Patty about the "warlocks" and she decides to come straight home, and bumps into Phoebe on the way out. Nicholas appears in a police uniform. Phoebe attempts to take care of him and kicks him down which flings his keys away. She runs into the diner to warn Prue and Piper. Nicholas follows, but the sisters have escaped.
The adult sisters sneak back into the manor. Avoiding Grams and Patty, Phoebe eavesdrops through a heating vent. Big Prue and Piper find little Prue and Piper and befriend them. A young Andy walks in wearing a cowboy outfit. He yells, "Freeze!" and little Piper freezes the room — freezing big Piper and Prue as well. Phoebe comes in to warn them that Grams is coming, but little Piper must unfreeze them first. She does so with a cock of her head, and they hurry out of the manor in Grams' car, but not before big Piper tells little Piper to buy them some time by freezing little Andy.
Grams comes down and finds little Andy frozen—apparently little Piper had a habit of freezing him. Little Andy tells Grams that "the strange ladies" left with little Prue and Piper.
The two sets of sisters play in a park. Big Prue throws a ball and little Prue and Piper use their powers to freeze and fling it. The police arrive and arrest the adult sisters.
Patty goes to a hotel room where she expects to see Victor. Instead, Nicholas ambushes her. She kicks him in the crotch and attempts to escape while he recovers. Patty is about to freeze Nicholas when he incapacitates her with his burning power. He tells her that she has an unborn child (Phoebe), and that she is the mother of the Charmed Ones. Patty realizes that Phoebe already had her powers in the womb—which explains her premonition. He presents the ring and demands that she bless it, making him immune to the Charmed Ones' powers.
Patty visits the adult sisters in jail and asks how they knew she was pregnant. The sisters admit the truth — they are Patty's daughters, come from the future to stop Patty's deal with Nicholas. She pays their bail. After an emotional reunion, the four return to the manor. They are too late to stop the pact, though.
Grams grills the adult sisters, asking them questions that only her real granddaughters can answer. She is at last convinced of their identities, and says that she knew either she or Patty would give birth to the Charmed Ones. Grams says she plans to bind the little sisters' powers once Phoebe is born, and doesn't understand how they got unbound—until she realizes she died shortly before the adult sisters regained them. The sisters are dismayed they couldn't stop the pact, but Grams tells them that they can only alter the past so much. She suggests that if they change the past incorrectly, much (if not all) of the good they'd done in their time might have never occurred. Patty suggests that there is something they can do—get the ring and let her un-bless it so they can defeat Nicholas in their time. She offers to go since the adult sisters are powerless, but Prue doesn't want to chance Patty dying.
The adult sisters find Nicholas' hotel room. Phoebe picks the lock and she and Prue enter as Piper watches for Nicholas. They bring the ring back to the manor. Grams and Patty prepare to send the sisters back, while Phoebe slips a note into the Book of Shadows, trying to warn Patty of her drowning death in 1978. Grams casts a return spell she just wrote, and nothing happens. Patty joins her in a second try, and this time the sisters disappear for a few seconds only. Piper figures they need the Power of Three, but it doesn't exist yet.
Patty proposes using the Power of Three via little Prue and little Piper. Nicholas comes in, demanding his ring. Grams flings him onto a table, then heads back to the attic. While Prue and Phoebe fend Nicholas off, Patty brings the little sisters upstairs. Grams says that Patty unblessed the ring, but they haven't had time to test it. The three chant the return spell, Patty standing in for the unborn Phoebe. Phoebe snaps a quick photo as the three chant. The spell sends the adult sisters back to the present.
Nicholas is still after them, but just as he is about to burn them again, Prue flings him across the room, the un-blessing worked. Piper freezes him while Prue and Phoebe find a spell. They find Grams wrote one, and even included a pouch with the ingredients for a potion. Phoebe speaks the spell, vanquishing Nicholas.
The sisters are again looking at the old photos, and find the one that Phoebe took before they were taken back to their time. Phoebe admits she wrote the note, but thought better of it and put it back in her pocket.
- Artifact of Doom: Nicholas's ring has been blessed to grant him immunity from the Power of Three.
- Batman Gambit: Nicholas made annual visits to the manor, deliberately dropping potted flowers in the presence of the sisters while the clock in the other room chimed. Every time was a test to see if the girls had gotten their powers back. Piper freezing the drop in The Teaser and the chimes playing out in full during the interim let Nicholas know his chance to claim their powers has finally arrived.
- Call-Forward: Young!Piper freezing Andy while playing prompts the sisters to joke about how suspicious he is of them in the present.
- Crouching Moron, Hidden Badass: Nicholas's disguise is that of a doddery old man.
- Evil Costume Switch: Nicholas switches his disguise of a harmless old man to his youthful self, wearing a suit, once he reveals himself as a warlock.
- Exact Words: Patty and Grams say the spell to move the sisters through time and space. It technically works, but it only moves them ahead of a matter of seconds because Patty and Grams lack the necessary power. This is why they have to use the younger versions of the sisters.
- Explain, Explain... Oh, Crap!: When the sisters say they just got their powers back and without the pact being broken, Grams says she'd never let that happen unless she died and then realizes that's what happened.
- Foreshadowing: Patty getting premonitions from unborn Phoebe foreshadows that pregnant witches will briefly have the powers of their unborn children.
- Have We Met Yet?: From the perspective of the time traveller. Phoebe gets to meet Patty and talk with her.
- Kid from the Future: In this case, it's the sisters themselves who are the kids from the future.
- Lampshade Hanging: Upon meeting Phoebe, Grams snarks, "Another P. What a surprise."
- Loophole Abuse: In the past, they're able to use the Power of Three with the younger versions of Prue and Piper. Patty fills in the third slot since she's pregnant with Phoebe and has already been getting premonitions.
- "Mister Sandman" Sequence: The opening scene is one big version with a montage of 1975.
- Ooh, Me Accent's Slipping: Finola Hughes's American accent slips quite a bit in her first appearance. She'd get better in subsequent episodes.
- Retcon: Phoebe says that a warlock will be the cause of Patty's death. The Season 2 episode that deals with her death shows that it was a water demon. Also, a form of Early Installment Weirdness, since warlocks were initially the main threat on the show. Even as early as Season 2, demons started to take their place.
- Secret Test of Character: A villainous version. Nicholas dropping the flowers turns out to be one. He visits every year to deliver flowers, and when he notices only three chimes on the clock, he realises that Piper must have frozen him - meaning the sisters have their powers back.
- Set Right What Once Went Wrong: Subverted. Phoebe wants to take advantage of the situation to warn Patty of her impending death and even writes her a letter, but she ultimately backs off out of concern for the rest of the timeline.
- Time-Travel Episode: The first of many in the series. Here when the sisters go back, they are there in addition to their past selves. Note that this differs from Clyde's spell in "A Paige From The Past" - where Paige assumes the body of her past self.
- You Can't Fight Fate: Phoebe attempts to stop Patty's death by warning her about the day she's supposed to die. After the spell to send the sisters back to the present fails, Phoebe removes the note and decides to leave history as it is.