Tinker Tailor Soldier Spy is a critically acclaimed 1974 spy novel by John le Carré. It follows the efforts of taciturn, aging spymaster George Smiley to uncover a Soviet mole in the British Secret Intelligence Service.
Cambridge Circus - John le Carré's "the Circus" (via London CyberPunk Tourist Guide):
N.B. it does not appear that "British Intelligence", certainly not the Secret Intelligence Service MI6, was ever really based at Cambridge Circus.
However, passages from Tinker, Tailor, Soldier, Spy, perhaps point to a more likely candidate building, just north of the actual Cambridge Circus cross roads itself.
Although MI6 is located elsewhere, le Carré’s gag was appropriate. For years, the secret service really had been little more than a circus, ostensibly born from Cambridge University stock yet Moscow-run.
“From his window he covered most of the approaches: eight or nine unequal roads and alleys which for no good reason had chosen Cambridge Circus as their meeting point. Between them, the buildings were gimcrack, cheaply fitted out with bits of empire: a Roman bank, a theatre like a vast desecrated mosque. Behind them, high-rise blocks advanced like an army of robots.”
