Continuity mistake: At the end of the episode, the doctor takes the mouthpiece out of Lex's mouth, then the scene cuts to Clark. When it cuts back to Lex, the mouthpiece is back in his mouth.
Continuity mistake: After Clark gets his powers back the cut on his cheek heals and leaves only blood on his cheek. While still at the power generator he goes to wipe this blood off of his face with the back of his hand only in the shot just before you see his hand go to wipe, a second before his hand actually appears on screen, the blood that was on his cheek is now gone as if it was already cleaned.
Continuity mistake: As Clark stands outside the room where Lex has just got his shock treatment the blood on his cheek is back even though his cheek wound was healed and he wiped any residual blood off in the previous scene at the power generator.
Continuity mistake: When Lex first tries to break out of Belle Reve, he stabs a security guard in the leg with a pencil deep enough to draw a large amount of blood on the guy's pants leg. But when Lex is trying to incapacitate the man you can see the pencil flopping around on the guards leg and not sticking inside the guy's leg.
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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