Plot hole: If Noah could be brought back from the dead with Claire's blood why couldn't they bring back Nathan? Was turning Sylar into Nathan really the first thing they could think of?
One of Us, One of Them - S3-E3
Revealing mistake: When Tracey looks at Nikki's dead body in the coffin (both played by Ali Larter) we can see Nikki's eyelids flicker.
Our Father - S3-E12
Continuity mistake: "Our Father". At the end of the previous episode, "The Eclipse, Part 2", Hiro brought Claire to the rooftop of the Deveaux building to witness Kaito handing over baby Claire to Noah Bennet. To illustrate his point, Hiro showed Claire the exact same thing happening in the "9th wonder" comic book he brought with him, and she can follow the Japanese dialogue from there. But when the exact same scene is shown at the beginning of this episode, Hiro does not show Claire the comic at all.
Other mistake: Peter rescues Angela from an elevator by flying her straight up the elevator shaft. When we see the shaft, it is completely devoid of any elevator cables.
Visible crew/equipment: When Daphne meets Linderman at pine hurst she walks to greet him and you can see a crew member behind a tree on the right side of the screen. (00:42:05)
Continuity mistake: When Sylar is impersonating Nathan, the knot on his tie keeps changing between scenes.
One of Us, One of Them - S3-E3
Factual error: When Hiro and Ando stand in front of a cinema in Berlin, Germany, you can see three movies posters in the background announcing a Buster Keaton festival. The left one shows his movie 'Cops' - but the German title 'Politzisten' is wrong - it should be 'Polizisten'. (00:09:55)
Continuity mistake: When Claire Bennett is cutting Peter Petrelli's chest she makes two cuts then the angle changes and the blood is gone, the angle changes again and it is back.
Continuity mistake: When Claire is looking at the "Alice in Wonderland" dust jacket, she holds in one hand looking at the back cover, then in the next shot, she's holding it with both hands looking at the front cover. (00:24:40)
Chosen answer: Because he's an idiot. From the story point of view, they needed the vault to actually be physically open so that the release of the virus would be a credible threat. Unfortunately, this required that Peter conveniently forget that he could simply walk through The Wall and use his telekinesis to tear the door open instead. Peter's increasingly large arsenal of abilities, where he ended up having pretty much any ability required for any situation, led to a situation where it became necessary to either have Peter apparently forget that he had a given power, as with the vault door scene, or become naively trusting, as with his refusal to scan Adam's mind to confirm his good intent. This problem, which simply made Peter look increasingly dumb as the show progressed, may well have been a key factor in the decision to severely reduce his ability during season three.
Tailkinker ★