The world knows him as hapless George Costanza of Seinfeld, but Jason Alexander has made no secret of his love for Star Trek—and so it’s no surprise he finally appeared in the franchise as Kurros, leader of the enigmatic namesake alien group of Voyager’s “Think Tank.” 

Born Jay Scott Greenspan in 1959 in Newark, N.J., he also returned to Trek fandom in a way by hosting Comedy Central’s roast of William Shatner. Alexander had a Tony-winning career on Broadway with Jerome Robbins’ Broadway and other titles before Seinfeld, and he co-starred in the original  Mel Brooks’ The Producers with Martin Short and A Christmas Carol with Kelsey Grammer. 

Alexander is also famous for his animation voices, with two cult favorites being the lead in Duckman and as Catbert in comic strip-based Dilbert. Although several of his live-action series have been short-lived, he has had memorable guest turns in series from Friends and Malcolm in the Middle to Everybody Hates Chris and Criminal Minds.

He is also currently the artistic director of Reprise! Theatre in Los Angeles, directing shows as well; his direction of a Brad Paisley country music video “Online” won a Country Music Association Video of the Year award. An avid poker player in televised events, Alexander won $500,000 on Bravo’s Celebrity Poker Showdown for the United Way to help post-Katrina New Orleans. He also supports OneVoice, the initiative to support peace efforts by moderate Israelis and Palestinians.