Harriet Hyde

Harriet Hyde is the secret alter-ego of Julia Jekyll.

Biography
Harriet Hyde was 'created' after one of Julia's experiments was sabotaged by the Blister sisters. Ever since this failed experiment, Julia has found herself uncontrollably transforming into Harriet Hyde.

Julia has made many attempts to try and rid herself of Harriet, usually with the help of her friend, Edward Knickers. She successfully created an antidote in the episode 'The Fingers of Mrs Figgis', however this was accidentally destroyed over the course of the episode, and Julia was unable to recreate the antidote.