Tark is an Argelian musician in Wolf in the Fold whose daughter Kara, a café dancer, is the first woman found stabbed to death with Scott standing over her.
Tark is a native of the pleasure planet Argelius II in the Original Series episode Wolf in the Fold. He plays in the café where his daughter Kara dances, and it is there that Kirk and McCoy bring Scott for some therapeutic shore leave.
Kara leaves with Scott for a walk in the fog. Minutes later she is found murdered and Scott is holding the bloody knife, with no memory of what happened. Tark is brought before Prefect Jaris with Kara's jealous fiancé Morla as the investigation begins.
Tark is angry and grieving, and he admits that he disapproved of Morla's jealousy, which Argelians regard as a shameful emotion. He attends the séance held by Jaris's wife Sybo, which ends in her death, and the later hearing aboard the Enterprise that exposes Hengist as host to the entity Redjac.