Continuity mistake: As Perry and Clark talk for the last time in this episode the sunlight in the scene changes between shots. As they step out of the truck the sun is behind them as they walk towards the road where the bus is going to stop. When Perry turns to face Clark the sunlight, which should now be hitting Perry right in the face, is instead casting a bright orange light on the back of Perry's head.
Factual error: Perry uses a simple black rope to tie himself to the railing by his ankle. This is not a bungee cord of any kind. He falls and is stopped, jerked to a stop actually, with both his weight and the weight of Clark pulling on his ankle. This would cause a very serious sprain if not an actual broken ankle yet Perry shows no signs of being injured when he and Clark walk to the bus.
Continuity mistake: As the telephone pole crashes falls on Perry's car the sky is bright blue with very widely spread clouds. Clark takes less than two seconds to get Perry out of the car and as he runs away from the car, with Perry in his arms, the sky now has many more clouds than before.
Audio problem: After Perry explains that the information he has on Lionel is with "multiple attorneys with 'in the event of my death' instructions" Perry tells Lex that the information is "all yours". As he says "all yours" the camera is behind and you can see Perry's mouth say "I just want one thing." but you don't hear Perry actually speak the line until the camera has switched and is facing Perry.
Audio problem: While Clark says "next time I could hurt you or mom." the camera is behind him. As he says "you or mom" his head is turned so that you can see his lips do not match the words being said.
Continuity mistake: In the previous episode, "Slumber," Clark wrecks the farm truck by falling asleep while driving. The car has massive damage that, at a minimum, would be extremely expensive and time-consuming to repair. Realistically, though, it is completely totaled. In the episode "Perry," the truck is again in brand new condition, like it was untouched.
Continuity mistake: When Perry arrives at the Kent's, and they start talking, Clark has his hands in his pockets. After being asked it he's a report, Perry starts to walk around and the shot changes and Clark no longer has his hands in his pockets and is then seen putting them in them.
Factual error: Tate fires at Clark, who is dressed as the drifter, 8-9 times from a revolver that is chambered for only 6 rounds.
Suggested correction: I count 5 shots fired, which is how he had 1 left that he was planning on using on himself. You must be counting ricochets or other sounds as shots fired.
Other mistake: In the flashback to 1961, "Splendor in the Grass" is playing at the Talon. However, the film was released in October of 1961 and Louise McCallum was killed in June of 1961. So the flashback would be set before the film was released.
Visible crew/equipment: When Lex and Chloe are talking after the morgue, you can see a crewmember passing behind her at 30:53. (00:30:53)
Suggested correction: You see a person walk behind her in a corridor. Since it is very obvious and occurs during a short cut where nothing else is happening, it is deliberate. A fundamental rule on film sets is that once "action" is called, no-one moves if they don't have to. If a crew member had walked through the shot like that, they would have done a new take or just use a different segment of the shot.
Continuity mistake: When Seth drops the spoon he was trying to control it drops into the portion of his tray that holds his jello cup. As Clark and Lana walk in the spoon is now in the part that holds the bread crusts.
Continuity mistake: When Seth is testing his powers in the hospital room he tries to move a cart at the foot of his bed. To do this he has to raise his hand to use the magnetic power he has. In shots from the front his right hand is palm down using his power but when the shot switches to behind Seth, to show the cart starting to move, his palm is now turned towards his left. His hand is back to being palm down when the shot switches back to the front.
Continuity mistake: As Lana is walking up the stairs to Clark's barn loft, from the front shot Clark has his hands to his side. When the camera jumps to behind Clark, watching Lana ascend the stairs as she says "I, uh, came by to say thank you." now Clark's right hand is behind his back and not to his side.
Continuity mistake: Martha is putting together a flower arrangement. When Jonathan is talking about Clark not eating the last piece of cherry pie, in a shot of Martha and Jonathan, Martha is picking up a branch of white flowers and holding it in front of her. When the shot switches to Clark, you can see her putting this same branch of white flowers in the vase even though she made no motion to do so in the previous shot. This is supposed to be continuous since you can hear Jonathan talking between the shots.
Continuity mistake: The first time Seth tries levitating a spoon, he floats it a few inches towards him. When Lana enters and breaks his concentration, it falls back down almost exactly where it had been.
Suggested correction: Even though it's impossible to tell how much the spoon moves towards him, the spoon was in the middle of the jello, then lands in front of the jello, a few inches away from the middle.
Continuity mistake: As Lana gets ready to throw the first ball there is a kid in a red, black and white shirt in the background and he is walking away from the scene. Just after she throws the ball the very same kid is calmly walking behind her again.
Continuity mistake: Seth fires at Clark and Clark dives behind a ride car to dodge the bullets. As Clark stands up he brushes the impacted bullets off of his shoulder. Seth says "Looks like I'm not the only one with special powers." before he turns to use his powers to pick up a ride car that is behind him. As Seth starts to get the car in the air, in the background you can see Clark is only just standing up and brushing his shoulder off again.
Revealing mistake: When Lionel Luthor visits the Kent Farm and tells the Kents and Chloe that Lex is missing, Allison Mack is laughing when the group is shown from Lex's viewpoint in the barn.
Audio problem: Lana pours Lex a cup of chamomile tea from a Thermos, however the cap is still on the Thermos, despite the sound of liquid being poured. When Lana moves the Thermos, the red dot on top of the plastic cap can be seen.