Sally Stukowski was an FBI agent who first appeared in the season opener "The New Guy," investing a murder case in Denver. She throws her weight around once she discovered Pete and Jinks working "her" case, and had the pair escorted out. After the case is solved, Sally thanks Pete and Jinks for their help, with the guarantee that the culprit will be caught. In the episode's final scene, however, the culprit is shown reporting to a mysterious man (later revealed to be Walter Sykes, the season's main antagonist), only to be suffocated with a plastic bag by Sally, who is officially revealed as a villainess.
After a brief appearance in the end of the episode, "Love Sick," the evil Sally resurfaced in the episode "Don't Hate the Player," calling Jinks on a suspected suicide, but it was actually a ploy to steal a Van Gogh painting. Sally's last appearance came in "The 40th Floor," where she is captured by the Warehouse 13 group after she killed regent Theodora Stanton. In her capture, Sally speaks in a normal voice and drops her fake Southern accent, while revealing that she's actually from Connecticut. She later escaped and reported to Sykes, who showed disappointment in her failure to kill The Regents, and she is later killed by Marcus Diamond.
- Ashley Williams also played serial killer Darlene Coolidge from Monk and conspirator Jo-Anne Kramer from The Protector.