(Volume Two: Generations) Four Months Later... - S2-E1
Continuity mistake: When Claire hugs Mr. Bennet she is holding her note in her right hand. In the next shot as she turns around and runs off to school the note is in her left hand.
Visible crew/equipment: When Claire runs away from Bob after he calls her "Ms. Bennet", you can see Bob's shadow and another person's shadow on the ground. Since no one else was standing next to them, it has to be a crew member, most likely a camera man based on the odd shape of the shadow.
Continuity mistake: Maya's necklace disappears between shots when she accuses Sylar of killing her brother.
Continuity mistake: When Alejandro finds Maya outside the tunnel, she has black ooze from her eyes running down her cheeks. As he starts his healing, we get a close-up shot of how the ooze fades and disappears from Maya's face. But in the next shot of her face, when she falls forward, the black stuff is back on her cheeks. It's gone again in the next shot of her. (00:29:20)
(Volume Two: Generations) Four Months Later... - S2-E1
Visible crew/equipment: S02E01 "Four Months Later". As the samurai warriors are about to engage the attack, a close-up shot of Hiro turning around reveals the white screen reflected in his glasses.
Continuity mistake: Right before Sylar shoot Maya, you can see she already has a bullet wound on her chest.
Factual error: In Season 2, Episode 3, Peter and the Irish family rob the bookmakers and the security guards shoot at them. In Ireland, even the police don't carry weapons. Let alone security guards.
Continuity mistake: When Maya is arrested, she starts manifesting her powers on the policeman. In a close-up, we can see the black ooze coming out of her eyes. Cut to a shot from above, when the policeman's eyes turn black and he drops the handcuffs, and Maya's cheeks are suddenly clean again, with no trace of the black stuff. (00:33:45)
Visible crew/equipment: When Mohinder, Sylar, Maya and Molly are at Isaac's old flat (now Mohinder's lab), as Mohinder and Sylar walk down the stairs, you can see the moving camera crane reflected in the glass behind them.
Continuity mistake: Season 2, episode 10, "Truth and Consequences": In the previous episode, "Cautionary Tales", when Noah was brought back to life he regenerated, then sat up, looked around him and said something sounding like "Home". In this episode, when the exact same scene is shown, we see Noah regenerating and sitting up, but this time he just looks straight ahead before lying back down, and does not say anything. (00:05:50)
Continuity mistake: Season 2, ep. 3, "Kindred". When Peter gets the box with his belongings back from the Irishmen, as Caitlin says "Well?" Peter's hands are in his lap. The angle changes to Peter, who answers "Well, what?" and he suddenly has both hands on the box, with no time to move them between shots. (00:35:55)
(Volume Two: Generations) Four Months Later... - S2-E1
Revealing mistake: After Kensei knocks Hiro down a goat licks Hiro's face. The kibble used to lure the goat in for the shot can be seen on Hiro's cheek and collar.
Continuity mistake: Season 2, episode 11, "Powerless":. In Mohinder's kitchen, when Sylar cocks the hammer of the gun he is holding on Mohinder, he is holding the gun with his arm straight and the gun completely level. The angle changes just as Sylar says "Maya, I need you to stay calm", and now his arm is close to his body and bent so the gun is pointing at Mohinder at an upwards angle. There was no time for him to move his arm in between shots. (00:03:30)
Factual error: When Nathan goes to Cork to find his brother, he gets out of a black cab with a yellow license plate, both of which are characteristic of ENGLISH taxis, not Irish ones.
(Volume Two: Generations) Four Months Later... - S2-E1
Factual error: In the scene where Hiro is in ancient Japan posing as Takezo Kensei to rescue the girl, what looks like a Gatorade bottle can be seen in the grass as they ride away. (00:18:45)
Continuity mistake: When Claire and West are talking about their abilities on the beach, the close up shots of Claire show that she is wearing earrings, the camera goes to West but when it focuses on Claire again she is no longer wearing them.
Chosen answer: Hiro's powers are still quite unreliable, and a locked closet door isn't a huge obstacle. Since Hiro knows he needs to rescue Ando, it's probably safer to try and bash the door down than risk teleporting to the wrong place or time.