Mary Ann Flagstarr is a character from the PKNA comic series. She is a federal agent of the PBI (Paperopoli Bureau of Investigation, being Paperopoli the Italian name of Duckburg).
Initially opossed to the Duck Avenger, she later begins trusting him and become friends. However, it isn't clear if that friendship is realy selfless, as Mary Ann doesn't doubt about using the Avenger several times to carry on dangerous missions, or using him to get Uno's help. The sense of being manipulated eventually has the Duck Avenger breaking any link with the PBI.
She makes her first appearance in PKNA 4: Earthquake. She oposses the Duck Avenger and tries to arrest him several times as the hero is investigating some top secret experiments on the west coast. The agent fights the masked duck until she discovers professor Morgan Fairfax's project Pangea, a mad visionary dream to destroy the entire west coast.
Agent Flagstarr re-appears in the 1997 special "Missing" investigating the Duck Avenger's disappearance. Later, in PKNA #17, the newly-promoted Lieutenant Flagstarr crosses paths with the superhero as they both look for Xadhoom, who is wandering Duckburg out of control.
In PKNA #21 Mary Ann asks for the help of the Duck Avenger and Uno because Fairfax has escaped from prison and allied with the Republic of Belgravia to complete project Pangea.