Guillam unexpectedly approaches Smiley in his home, and takes him to the house of Under-Secretary Oliver Lacon, a Civil Servant responsible for overseeing the Circus. There, they meet Ricki Tarr, a Circus agent who has been declared "persona non grata" due to suspicion of having defected to Moscow. Tarr presents his defence, explaining that he was informed of a Soviet mole, codenamed Gerald, at the Circus' highest level whilst in Hong Kong by Irina, the wife of a trade delegate who he was surveiling. Irina explained to Tarr that Gerald reports to a Soviet official stationed at the embassy in London called Polyakov, and that he should communicate this to the Circus' new head, Percy Alleline. Shortly after Tarr relayed this to the Circus, however, Irina was forcibly returned to the Soviet Union, leading Tarr to realise that not only was the mole real, but also now knew his identity. As a result, Tarr entered into hiding, resurfacing only to contact Guillam, whom he knew he could trust.