The Lost Chord
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The Lost Chord was a sequence of musical notes that incorporated The Devil's Chord. It had the power to summon Maestro to the universe. Another sequence of notes, also referred to as "The Lost Chord" by Maestro, and alternatively, the "Notes of Banishment" by the Fifteenth Doctor, had the power to banish them from the universe.
In 1925, Timothy Drake discovered the first sequence, summoning Maestro. Later, in 1963, the Doctor almost discovered the second sequence, before fumbling the final note. John Lennon and Paul McCartney then completed the sequence, banishing Maestro. (TV: The Devil's Chord [+]Loading...["The Devil's Chord (TV story)"])
