Continuity mistake: When Jason starts knocking on Lana's door, the clasp from the door chain is all the way to the left. The camera cuts to Lana in bed. When it cuts back to the door, the clasp is now all the way to the right.
Revealing mistake: Kristin Kreuk's body double in the shower scene is noticeable. She is slightly larger and differently shaped.
Continuity mistake: When Kal-El/Clark pushes Martha away her hands are down around her chest. The shot changes, as Kal-El builds up power to fly, and now Martha's hands are spread out away from her body.
Factual error: There is a snow pattern on the Quicktime player after Chloe's message to Clark finishes. She would have recorded in on a camcorder, so there wouldn't be any snow pattern, it would be a blue or black screen. The only way there could have been is if she recorded it, put it on VHS, then copied it back onto a DV tape, then transferred it back onto her computer, but there's no reason for her to do this.
Continuity mistake: While Martha reads to Jonathan, as he is in a coma, the light on his hands change. In the shot from the right side of Jonathan's bed his hands have only a normal level of light like from a small table lamp. The shot changes to look at Jonathan from the doctor's point of view and suddenly Jonathan's hands are very brightly lit like from a spotlight. No one changed or turned on any other lights between shots.
Answer: In the comics, Krypto is a dog from Krypton who was used as the passenger in a test launch by Jor-El, Superman's father, before he launched the actual rocket taking his infant son to Earth. Krypto's capsule was involved in a mishap, sending it out of Kryptonian orbit and eventually found its way to Earth where he linked up with the young Clark Kent. Like any native of Krypton, Krypto has superpowers on Earth. In Smallville, the dog is a standard Earth dog who has been experimentally injected with kryptonite, giving him super-strength for a limited period of time, who escapes and links up with Clark (who suggests the name Krypto, ostensibly because of the dog's cryptic origins). It doesn't take too long for the dog's strength to fade, and the Kents decide to keep him, although they ultimately name him Shelby, after a dog that Martha Kent had in childhood.
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