Size Matters - S4-E5
Continuity mistake: Shortly after Phoebe frees the blonde girl from the clay, she tells her to run "before Gammill sees [them]." But Phoebe hadn't learned the demon's name at any point. Leo and Piper do find out his name, but not until later. (00:20:00)
Suggested correction: Gamill and Finn are talking when Phoebe is at the house. It may be possible that Gamill's name was mentioned by Finn in conversation.
Continuity mistake: After Phoebe jump kicks a warlock and falls to the ground, there is a blonde woman standing next to them. In the next shot of the warlock, when Piper blows him up, the woman is gone. But all of the mortals had been frozen, so she couldn't have moved. (00:37:40)
We're Off to See the Wizard - S4-E19
Continuity mistake: In the scene where we first see Phoebe and Cole when she's about to leave the apartment, you see she is wearing gold and white high heels but as soon as she reaches the elevator she's wearing black boots.
Continuity mistake: Piper does not light the candles before she summons Grams, but in the episode 'PreWitched' (when Grams summons Patty) we see that the candles must be kept alight to maintain the connection with the dead. (00:18:00 - 00:33:30)
Continuity mistake: Paige looks in the Book of Shadows and suggests that the demon they are looking for could be Belthazor, not knowing that Belthazor is Cole's demonic form. But we saw Phoebe making extensive changes to Belthazor's entry in the Book of Shadows in a previous episode, and the changes are not in evidence here. (00:01:40)
Size Matters - S4-E5
Continuity mistake: Piper suggests that Paige orb in place, because the clay is still wet enough that it will collapse if she's not there to support it. But when Paige actually does orb, the clay cracks and collapses into powder as if it had been bone dry.
Continuity mistake: After Phoebe has her premonition about Paige at Prue's funeral, demonic bounty hunters show up to "eliminate" Belthazor. We see the funeral hall empty where seconds before Phoebe's premonition, there was a line of people waiting to give their condolences to the girls, Victor, Leo and Cole. (00:12:20 - 00:13:10)
Continuity mistake: The name plate under the photo of Leo at the Veterans Association indicates that he died on November 24, 1942. Paige's research indicates that Nathan and Rick both died on the same day as Leo, but she later finds out that they were buried at the V.A. on November 22, 1942, two days before they are supposed to have died.
Continuity mistake: During Prue's funeral when the demonic bounty hunters attack, one gets thrown into some chairs, which knocks some down. When we see the chairs again in another shot the ones left standing and the ones knocked down have changed. (00:13:25)
Continuity mistake: If Leo can't hear the girls call him when HE is underground, he shouldn't be able to hear the girl's call him when THEY are underground and he doesn't know they are at P3 until a few minutes later.
Continuity mistake: In this episode, an invitation to Piper is addressed to 1329 Prescott Street. But in episode 1-7: "The Fourth Sister," the Halliwell sisters put up a flyer for their lost cat, and it gives their address as 7571 Prescott Street.
Continuity mistake: Near the end of the episode, in the scene at P3, Phoebe launched a jump kick at a warlock after Paige has been knocked down by a small energy ball. Everybody else in the club was frozen by Piper, but when Phoebe lands she jostles a blonde extra who moves from her pose.
Continuity mistake: After Phoebe and Paige have switched bodies and Phoebe is trying to teach Paige how to levitate, Phoebe's hair switches from her shoulder to her back then to her shoulder again. (00:20:15)
Continuity mistake: When Paige was invisible and Cole watched the blood, there was a large pool of her blood, but in the next shot, the pool of blood was smaller. (00:36:00)
Continuity mistake: In the scene where Agent Jackman shows them the file he has on them in their dining room, Paige's left dress strap has fallen off her shoulder in some shots, but in others it's perfectly in place.
Continuity mistake: In the teaser, Phoebe has a vision of a murder. When she first sees the shadow of the attack, the assailant is holding his victim down with his right hand while stabbing with his left. Then when the vision focuses on the Medusa head tattoo on his forearm, it is the right arm that is stabbing. (00:04:15)
Continuity mistake: After the "dirtbag" is brought back to the manor and Piper is ragging on him, Piper gets very angry and decides to blow her husband up. Less than a minute later, Cole says "Back away slowly, Leo." Leo says "What?" and Cole says "She's becoming a fury." Then it shows Pipers hands, which now have long black fingernails, but they just suddenly show themselves right when Cole decides to show up and say she's becoming a Fury. When she blew Leo into orbs there were no long black nails. (00:25:35)
Continuity mistake: In the church scene when Phoebe and Piper are showing Paige how to use her power, Piper says "according to the prophecy, the third sister has the power to move things with her mind, like Prue could." Prue was not the third sister, but the first. Paige is technically The Fourth Sister, but since the prophecy didn't speak of a "Power of Four", she would automatically become the third sister after Prue's death. (01:02:42)
Continuity mistake: During the opening, Piper, Phoebe and Cole are in an SUV and going to find a demon. A shot from in front shows that there is no rearview mirror in the SUV, just a white mark on the windshield. When they turn into the parking lot however, the rearview mirror has returned.
The Three Faces of Phoebe - S4-E14
Continuity mistake: When Phoebe casts the spell to hear her hearts desire about marrying Cole it conjures old Phoebe and young Phoebe. When Leo, Piper, and Paige enter the room they all room perplexed by who the two people, just conjured, are. If this is supposed to be young Phoebe, wouldn't Leo (who has followed all them their whole lives) Piper and especially Phoebe recognize the younger Phoebe immediately instead of being confused by who she is?