Grathon Tolar was a skilled holographic forgery artist and con-man.
In 2374, Tolar was awaiting execution in a Klingon prison for unspecified crimes. Benjamin Sisko contacted Chancellor Gowron to arrange a pardon for Tolar. Under the conditions of the pardon, Tolar had to create a holo-program for Sisko. The program was a faux recording of a high-level Dominion meeting in which the supposed plan for the invasion of Romulus was discussed.
Before Tolar could complete it, he was involved in an altercation at Quark's. Sisko was forced to bribe Quark in order to have the charges dropped. When he did finish it, the recording did not fool Romulan senator Vreenak. Vreenak took the evidence intending to return to Romulus, but his shuttle exploded on the way from a bomb placed there by Elim Garak. Garak then killed Tolar so there would be no witnesses to the operation.