She is extremely politically ambitious, serves as non-executive director on 5 QUANGOs (quasi-autonomous non-governmental organisation), and has many contacts in the British civil service and government. Lady Ty resents The Folly's 'interference' in the affairs of the Genius loci and the Demi-monde. She seeks to end the role of the Folly as intermediary and replace it with a 'Ministry of Magic' according to Peter Grant.
She is not averse to using her magical power and political influence to achieve her ends. However, she is obedient to her mother, Mama Thames. Her genius loci predecessor under Father Thames, Sir William of Tyburn, has appeared multiple times to Peter.
She attended St. Hilda’s College, Oxford University during the 1990s and received a double first in History and Italian. During this period she observed multiple members of the Little Crocodiles Dining Club, whose use of Newtonian magic she claims she could 'smell'.
She lives in Chesterfield Hill, Mayfair with her hydrogeology civil engineer husband ,George McAllister-Thames, and two children. A eighteen-year-old son called Stephen George McAllister-Thames, and a 16/17 year old daughter named Olivia Jane McAllister-Thames.
Sir William of Tyburn
See Main Article: William of Tyburn
The original genius loci of the Tyburn river--Sir William of Tyburn), was one of the sons of Father Thames. He died as a result of the river pollution of the Victorian era (during the Great Stink in 1858).
Although Sir William died in 1858, his ghost continues to manifest in the present day. The timing and reason for these manifestation is unclear. Peter Grant theorized that ghosts of old Genius loci are folded into the existence of the new Genius loci. Lady Ty herself confirms that his memories are part of hers. She is later able to put Peter into a trance-like state so that he can talk to William of Tyburn about Punch. 
Relationship with the Folly
Lady Ty is dismissive of the Folly and the role it plays mediating affairs between the demi-monde, and the non-magical UK populace. She considers it an archaic institution but is unable to circumvent the agreement between her mother and the Folly.
Genius Loci Attributes
Lady Ty's personality is tied in with the attributes of her river. Peter has describes her vestigium as 'old rope'--a reference to the Tyburn Gallows; cigar smoke--a reference to her political influence; fresh fish cooked over an open fire.
For many centuries, the name Tyburn was synonymous with capital punishment, it having been the principal place for execution of London criminals and convicted traitors. The Tyburn gallows stood in the middle of the roadway, providing a major landmark in west London and presenting a very obvious symbol of the law to travelers.
In 1571, the Tyburn Tree was erected at the junction of today's Edgware Road, Bayswater Road and Oxford Street, near where Marble Arch is situated today. The "Tree" or "Triple Tree" was a novel form of gallows, consisting of a horizontal wooden triangle supported by three legs which allowed several felons to be hanged at once. The title of the book The Hanging Tree is a reference to this structure.
Cecelia Tyburn McAllister-Thames makes a brief appearance in Low Action, the fifth novel in the Vinyl Detective series written by Andrew Cartmel.
- The Hanging Tree
- Moon Over Soho
- Rivers of London
- The Hanging Tree
- Lies Sleeping
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