During the Cardassian Occupation of Bajor, Trentin was an informer for the Bajoran Resistance, though she was never officially a member. She worked as a cleaner at a Cardassian records office in Dahkur Province, from where she secretly passed information to the Shakaar resistance cell for years without being discovered. The information she gathered made it possible for the Shakaar cell to mount dozens of attacks on Cardassian targets. She never stopped helping the Resistance, but spent every day terrified that she would be caught by the Cardassians. Her fear was so great that even after the Occupation ended she did not want it to be known what she had done.
Trentin was murdered in 2373 by Silaran Prin, part of a campaign of killings that Prin perpetrated in revenge for the assassination of Gul Pirak by the Shakaar cell during the Occupation. Prin used a remat detonator to kill Trentin during rematerialization as she transported aboard a runabout that was to take her to Deep Space 9 for protection. Trentin had passed information to the Shakaar cell that allowed them to bypass the security systems of the Cardassian weapons depot outside Hathon where Pirak was stationed, and thus carry out the assassination. Because of her actions, Prin regarded Trentin as guilty and killed her in order to bring her to justice. (DS9: "The Darkness and the Light")