Rudolph first appears as a rookie cop in the S.I. department of the Chicago Police Department. At first, he doesn't believe in the supernatural and keeps asking if the loup-garou is a prank for the rookie. He later transfers to Internal Affairs[Footnote 1] and makes several appearances throughout the series, most of the time trying to expose Harry Dresden as a fraud or get Karrin Murphy fired.
In the series
In Fool Moon, Rudolph is described as a young, good-looking rookie with short dark hair and a tense panicky voice.(reference needed)
Shortly after shooting Harley MacFinn with twenty-two caliber silver bullets, Karrin Murphy arrests Harry Dresden and passes custody to Rudolph during the loup-garou attack in the Special Investigations offices. Rudolph isn't handling this paranormal encounter well, rationalizing that the loup-garou is a prank to scare rookies and that Dresden is a fake, and is boggled by Dresden's strange request for elements for a Thaumaturgy spell. Rudolph, still confused, retrieves a Snoopy stuffed animal from the main offices. The Loup-garou then charges into the holding cell, and kills several SI cops, including Ron Carmichael. After causing chaos, the Loup-garou flees the building and Dresden orders Rudolph to direct emergency personal to this floor to help the wounded. Rudolph in shock, does so, and Dresden begins performing the Thaumaturgy spell.(reference needed)
In Changes, Rudolph points FBI Agent Barry Tilly at Harry Dresden, after Dresden's office building explodes, suspecting him to be behind the explosion. Dresden suspects that Rudolph is someone's puppet. Dresden and Molly Carpenter stake out his house—which is notably nicer than a police detective's salary should have been able to afford—to catch his "handler/cleaner", which turns out to be Esmeralda and Esteban Batiste. They had hired Rudolph and brought an Ik'k'uox to kill him. Later, at FBI Headquarters, Rudolph harasses Murphy and Dresden, threatening to take Murphy's badge and weapon. Just then, the Eebs attack with a vampire troop and the Ik'k'uox. Rudolph freaks out and becomes unresponsive. Agent Tilly is put in charge of him while Dresden and Susan Rodriguez organize the escape from the vampires.
In Battle Ground, on the way to Castle Marcone Harry Dresden is stopped by Detective Bradley and Rudolph, who want to detain him. Dresden and Bradley exchange a soulgaze, and Bradley staggers, distressed by what he saw. Rudolph draws his gun and accuses Dresden of attacking his partner, who holds his position while commenting on Rudolph's poor trigger discipline. Bradley recovers, telling Rudolph to stand down and let Dresden go.
At the childcare center, Dresden discovered Bradley and Rudolph defending it, and Bradley has to knock Rudolph out to get everyone to cooperate with the evacuation. However, Bradley isn't able to carry both his daughter and Rudolph, so Dresden has him leave Rudolph and escape with the Alphas and the other children while he and Murphy hold off Svangar, a Jotun who survived Thor[Footnote 2] himself. Dresden barely survives Svangar, until Murphy kills him with a rocket launcher. Their victory is short lived however, as Rudolph soon awakens and fatally shoots Murphy by accident, due to poor trigger discipline.
Murphy tries to tell Dresden she loves him, but dies before she can complete the sentence. Dresden doesn't believe his eyes at first, but when he does, he attempts to kill Rudolph. He nearly crushes Rudolph to death with kinetic force before Sanya and Waldo Butters are able to stop him.