Yasen Peyankov (born 1963) is a distinguished Bulgarian-American actor, director, and educator who has become a cornerstone of the Chicago theater scene and a recognizable face in prestige television. A graduate of the National Academy of Theatre and Film Arts in Sofia, he immigrated to the United States in 1990 and co-founded the European Repertory Company before becoming an ensemble member of the world-renowned Steppenwolf Theatre Company in 2002. Peyankov is widely celebrated for his versatility and intellectual depth, appearing in numerous Steppenwolf productions such as The Cherry Orchard and The Brother/Sister Plays. His film and television career is marked by notable roles in Stranger Things (2022), where he played the pivotal character Oleg, as well as appearances in Succession, Chicago P.D., and the film Captive State (2019).