Born in the Soviet Union, Gessen's family emigrated to the United States, where they spent them teenage years before returning to post-Soviet Russia. In Moscow, they worked as a science journalist for the popular magazine Vokrug Sveta and was an activist for the LGTBI community.

As a result of his advocacy for freedom of expression and LGBTI groups in Russia, they became one of the most visible faces of the opposition to Putin, and returned to the United States in 2013. Since 2017, they have been on the editorial staff of The New Yorker and, since 2020, they have been teaching writing at Bard College in New York. They are also a contributor to The New York Times and The New York Review of Books, among others.

Them books include El hombre sin rostro. El sorprendente ascenso de Vladimir Putin (Debate, 2012), El futuro es historia. Rusia y el regreso del totalitarismo (Turner, 2018), National Book Award for non-fiction in the United States, in which they highlight the democratic setbacks of the current Russian government, and Sobrevivir en la autocracia (Turner, 2020), a testimony on the workings of totalitarianism that was revealing before the arrival of Donald Trump to the White House in 2016.