Chall was a female Bolian in the late 24th century. She joined the Federation Department of Temporal Investigations in 2363, becoming a field agent. Early in 2369, Chall and her new partner, Agent George Faunt, were negotiating with Agent Revad of the Romulan Temporal Assessment Group, hoping he would share information about the rumoured transmissions received in 2351 by one Telek R'Mor from a Federation starship, then two decades in the future.