Shepherd, Dan (Fictitious character) -- Fiction. Criminal investigation -- Fiction.

Shepherd, Dan (Fictitious character) -- Fiction. Undercover operations -- Fiction. Great Britain. MI5 -- Officials and employees -- Fiction.

Prisoners -- Fiction. London (England) -- Fiction. Suspense fiction.

Demonology -- Fiction. Nightingale, Jack (Fictitious character) -- Fiction.

Shepherd, Dan (Fictitious character) -- Fiction. Undercover operations -- Fiction. Suspense fiction.