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Mona Lisa's Revenge is the fifth serial of the third series of the British science fiction television series The Sarah Jane Adventures. It first aired in two parts on CBBC on 12 and 13 November 2009.
Plot
Luke enters Clyde's painting for a competition and Clyde wins first prize. The prize is a trip for Clyde and his class to see the first showing of Leonardo da Vinci's Mona Lisa in Britain. Due to her proximity to her "brother", a painting known as the Abomination that was painted with the same kind of sentient paint in the same neighbourhood, Mona Lisa comes to life and steps out of her frame. She asks the curator Lionel Harding to find the Abomination, which is locked away in a box in the gallery's basement. Seeing the coverage of the supposed theft of the painting on television, Sarah Jane arrives at the gallery, encounters Mona Lisa and insists she release those transferred into paintings. Instead, Sarah Jane herself is trapped in a painting.
The key to the box is a puzzle box located in the gallery. Despite his admiration for Mona Lisa, Lionel destroys the key to prevent her from unleashing the Abomination on the world. Luke has Clyde draw a recreation of the key, which is in the same sketchbook as a sketch of K9. Mona Lisa brings the key into reality and opens the crate containing the Abomination. Before the Abomination can escape, K9 also comes to life and fires at the beast, causing it to retreat into the vault. Mona Lisa reverts to being a painting in a picture frame, and Sarah Jane and the others trapped in paintings are released.
Continuity
The majority of the episode is set in The International Gallery in London, the same gallery where companion Lady Christina De Souza stole the Cup of Athelstan in the Doctor Who episode Planet of the Dead, as the incident was referred to as "the Cup of Athelstan fiasco at Easter".
The Abomination itself manifests as a horned demon, similar to "The Beast" from Doctor Who story "The Satan Pit" and Abaddon from Torchwood story "End of Days".