She worked with fellow detectives Javier Esposito (Jon Huertas) and Kevin Ryan (Seamus Dever) and medical examiner Lanie Parish (Tamala Jones) under Captain Roy Montgomery (Ruben Santiago-Hudson).

In "Always", Beckett resigns from the NYPD after nearly losing her life trying to apprehend Cole Maddox, the sniper who shot her the previous year at Captain Montgomery's funeral.

She asks for her old job back, and because her resignation wasn't processed, Captain Gates allowed her to remain on the force after serving out the suspension she was assigned for disobeying orders.

In "The Human Factor", Beckett is headhunted by Jerry Stack, a special investigator for the Office of the United States Attorney General, who offers her a job in Washington, D.C. where she will work on the most challenging and sensitive cases in the country.

However, although Beckett made a positive impression on her colleagues for her investigative skills, she soon found herself unable to make the necessary moral compromises for her new role, jeopardizing a plan to infiltrate a major crime syndicate to protect a young woman who would have been forced to act as the mole.

As a result, Beckett was fired, leaving her briefly unemployed due to station budget cuts preventing Gates from simply re-hiring her.

Despite this, Castle was able to get her job back after he helped to reunite a prominent politician with his long-lost daughter in "Number One Fan", the city official wanting to thank the team for their role in bringing his family together.