Continuity mistake: Carly and Sam stick their heads in buckets of water to stay awake. Their heads and clothes are wet during the whole scene, but when the show comes back from commercial, their hair and clothes are completely dry.
Continuity mistake: During the attempted record-breaking webcast, when Spencer is seen explaining his sculpture on the studio's screen the red leaf blower falls backwards, but when he is seen live the blower has fallen forward.
Answer: In direction translation it means 'Mischievous Spirit'. 'Hob' as in HobGoblin means clown or prankster, and 'Knocker' was an old age term for Poltergeists in mines. Miners would often complain of hearing knocking sounds down mines when there was no-one else down there, hence 'Knocker'. It's not a regular English expression though.
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