Denise Crosby
Denise Crosby

Denise Crosby played Tasha Yar, the chief of security and tactical officer. Crosby left the series at the end of the first season when Tasha was killed off.

She returns in alternate timelines in the award-winning episode “Yesterday’s Enterprise” and the series finale, “All Good Things…”. Crosby also played Commander Sela, Yar’s half-Romulan daughter.