High Seeker commands the Seekers of Truth as Lord Seeker, serving as the direct superior and mentor to both Cassandra Pentaghast and Byron. He spearheads the Seekers' investigation into a blood mage cult responsible for kidnapping the young elven mage, Avexis. Following her initial rescue, he refuses Circle demands to return Avexis, convinced she possesses crucial information about the cult's rituals and goals, prioritizing uncovering wider conspiracies over Circle protocols.

He reports on the Seekers' actions against the cult during a formal audience with Divine Beatrix III and other Chantry leaders. There, he dismisses Knight-Commander Martel's concerns about operational methods, asserting the order's independence. When Cassandra and Avexis subsequently vanish under suspicious circumstances, he initially resists Templar involvement in the investigation, trusting Cassandra will eventually justify her actions.

After Cassandra and the Circle mage Regalyan D'Marcall evade capture, they confront him directly with evidence exposing a conspiracy involving corrupted Templars and Chantry officials. He reviews their findings, including an Elven stone containing transcripts of incriminating conversations between Knight-Commander Martel and the blood mage Frenic. Convinced by this proof, he agrees to present their claims to the Divine. Moments later, Martel ambushes and murders him, framing Cassandra and Regalyan for the killing. His death occurs shortly before a planned attack on the Chantry leadership during its ten-year gathering celebration.

The High Seeker exhibits a measured leadership style favoring strategic discretion. He demonstrates adaptability, shifting from pursuing Cassandra to supporting her claims upon reviewing concrete evidence of the conspiracy. His name remains unstated, identified solely by his formal title.