Gabriel Petrovich Beloszoksy (Polish: Gabriel Białystoki; Russian: Гавриил Петрович Белостоксий) also known as Semyon Andreyovich Petrov (Russian: Ceмен Андреевич Петров) is a former KGB handler to Elizabeth and Philip Jennings. He was initially assigned to them before the Center sent them Claudia; after getting complaints about Claudia and losing Kate, the Center reappoints Gabriel to his former position. ("EST Men")
He has a close relationship with the Jennings, built on trust and admiration, but the pressure to recruit Paige Jennings puts a wedge between them, especially with Philip, who doesn't want to indoctrinate Paige into the KGB. Over time, he sees the toll the missions take on the Jennings and has the Center not assign new missions to them for nearly a year. ("The Magic of David Copperfield V: The Statue of Liberty Disappears")
Exhausted with the work, Gabriel returns to Moscow and Claudia is reinstated as the Jennings' handler. ("The Committee on Human Rights") Gabriel was born Semyon Andreivich and is likely from Sergach, where he retired the first time. He never married, but did have a few distant relatives.
Not much is known about Gabriel's life, other than that he grew up in a serious generation, when times "were bad." He remarks that his life before the war was marked by constantly being afraid, and he often acted out in fear for his life.
Despite the first attempt at the Second Generation Illegals going horribly wrong, the Center requests that Paige be recruited for the Soviet cause. This causes tensions to rise between the Jennings and Gabriel, because Philip is vehemently opposed to the idea (even threatening to leave the KGB if they approach her ("Echo"), while Gabriel and Elizabeth are more willing to do so, albeit slowly. The three of them are rarely able to discuss the matter as a group without Philip becoming too enraged and storming out, declaring Paige is “not equipped to deal with this shit.”
When Paige finally discovers the truth, Gabriel eventually meets her as part of her indoctrination. However, after witnessing the work of her parents rip away at them, Gabriel later regretfully remarks that Philip was right about Paige – that she would’ve been better off being kept out of the KGB’s dealings.
Gabriel has a fairly strong relationship with Elizabeth
and Philip, but unfortunately, his bond with Philip becomes strained when the Center insists on Paige learning about her parents’ identities. Elizabeth seems more open to the idea, and she is able to talk to Gabriel about her progress with Paige much more freely.
Philip and Gabriel’s relationship begins to fall apart because Philip feels Gabriel (and the Center) consistently ask too much of the agents without remuneration, and what they ask is breaking the trust between agent and handler. The fallout starts with the pressure to tell Paige the truth, something Philip never wanted. When Elizabeth goes ahead with the mission, Philip takes some of his anger out on Gabriel, telling him, “I trusted you. Your job was too look out for me. And now my job is too look out for my family because no one else will.” The Center then calls for Philip to start a relationship with 15 year old Kimmy, and Gabriel insinuates that Philip should sleep with her if the mission calls for it, further breaking the trust between the two, as Philip is greatly depressed and disgusted with his missions. Gabriel sees this and even tells Elizabeth he feels Philip is “losing faith” in him, which is confirmed when Philip goes behind the Center's back and arranges for Elizabeth to meet her dying mother. This annoys Gabriel and he finally tells Philip that he needs to “grow up.” He later confides in Claudia, though, that he “can’t help wondering if Philip is right” about keeping Paige out of the KGB, saying that the partnership between the Jennings had been stronger than ever before that is ordered.
He visits Martha to check up on her in Moscow. She bitterly tells him she “understands” everything now, and then asks him not to see her again. ("IHOP")
Gabriel has a less hands on approach to being a handler compared to Claudia, having fewer meetings, but over dinner and a scrabble game within safe houses rather than quick chit chats in cars.
Whether due to his age or just a part of his own demeanor, Gabriel moves along at a glacial pace and tends to take his time with his words and agents. He is caring and understanding towards his agents, noticing when the Jennings’ have just about reached their limits and making the Center let them slow operations to allow them to recuperate. At the same time, he is also dedicated to his work and continually directs his agents towards the mission objective, like coercing William Crandall to steal Lassa virus and encouraging the Jennings to bring Paige into the fold. He is clever and enjoys words, as he tells Philip; he often plays Scrabble during meetings. The Jennings also remark that Gabriel is a wonderful cook, something they missed when Claudia was first assigned to them.
- When Paige was young, Gabriel gave her a stuffed, toy tiger which she named "Jessie." He has a cousin in Leningrad and a nephew in Sverdlovsk. ("The Committee on Human Rights")