Voskovec began his career in 1927 by forming a partnership with Jan Werich. Together they wrote and performed 26 productions for the Liberated Theatre of Prague over 11 years. He emigrated to the US after the German invasion, making his Broadway debut in 1945 in The Tempest.
He returned to Prague after the war but later settled in America. His film career included roles in 12 Angry Men 1957, The Spy Who Came in from the Cold 1965, and The Boston Strangler 1968. He also appeared in television series such as The Fugitive and Hawaii Five-O.
Voskovec won an Obie Award for his performance in Uncle Vanya and continued acting into the 1970s, including a role in Samuel Beckett’s Happy Days.