She is a community college physical training (PT) instructor from Xenia, Ohio (one of the women whom Redman's party rescues from the harem in the revised–expanded version). While she originally seems to show some level of romantic interest in Stuart Redman, this does not extend beyond flirtation and the two kiss before, like Susan Stern, she leaves to spy on the West coast. Jurgens' affectionate behavior towards Redman causes Fran Goldsmith feelings of consternation—later, it is revealed that Jurgens is bisexual.
After residing in Boulder for a short period, Stern recruits Jurgens—both were fellow captives in the harem from the revised–expanded edition of the book—to spy on the West coast. In Las Vegas, Jurgens works with a streetlight-repair crew and sleeps with Lloyd Henreid as part of her job to get information. While working with the crew, she observes Tom Cullen on a passing truck. Randall Flagg, aware of her identity through telepathy, summons her to his office and attempts to make her reveal the third spy, whose mind he is unable to penetrate. In order to protect Cullen, and to save herself from torture at the hands of Flagg, Jurgens commits suicide by first crashing her head through a plate-glass window, and then taking advantage of the sharp edges of the broken glass to slice open her jugular vein. This act of free will indicates the beginning of Flagg's downfall, as, while he foresaw her attempt to kill him and consequently stopped the attempt, he did not predict her suicide attempt and could therefore not prevent her death. Jurgens' body is later desecrated by Flagg and then burned outside of Las Vegas.
In the miniseries, Dayna is portrayed by Kellie Overbey. She is not rescued from the harem, instead being in a relationship with a man named Mark when she is found by Redman's party. Mark later dies of appendicitis, depressing her, mixing her role with that of Perion from the novel.