Natasha Yar was a major character during the first season of Star Trek: The Next Generation. She was portrayed by actress Denise Crosby and the character served as the chief tactical and security officer aboard the USS Enterprise-D until Crosby left the show near the end of season one.
The back story for the character states that Natasha (Tasha) Yar (Ukrainian: Наташа "Таша" Яр), of Ukrainian descent, was born on Turkana IV, a colony that fell into chaos and eventually severed ties to the United Federation of Planets. Tasha learned to defend herself on the streets and avoid rape gangs. She left Turkana IV at age 15, leaving her younger sister Ishara behind, and later attended Starfleet Academy.
After watching Yar cross a minefield to save a colonist, Jean-Luc Picard requested that she be assigned to his next command. She later became chief of security and chief tactical officer aboard the USS Enterprise-D, some time prior to the beginning of the series.
Tasha was killed in late 2364 on the planet Vagra II. She was part of an away team sent to rescue Deanna Troi and Ben Prieto, who had crashed there aboard a shuttle. Their rescue was impeded by a lifeform known as Armus. When Yar tried to walk around Armus to get to the shuttle crew, Armus attacked and killed her without warning, simply as a display of his power. Dr. Crusher tried to revive her but she was too badly injured, as the life had been "drained" from her. The officially recorded cause of death was heavy synaptic damage. A service was held for Tasha in the holodeck following the rescue of the crew from the surface, where a holographic message from Tasha was played. Tasha always believed her death would happen quickly and while on duty, and that was the way she wanted it.