Secret Diary of a Call Girl: Season 3 (2010)

In the third-season opener, Belle goes incognito to her book's launch party to gauge reaction to her roman à clef. Her editor, Duncan (James D'Arcy), tries to coax her into writing a follow-up novel, but she fears she doesn't have enough material for a sequel. In the glow of her success, some darkness falls upon Belle's door with the unexpected arrival of her sister Jackie (Joanna Bobin), who's left her cheating husband and seeks a place to crash.

In an effort to help Jackie better understand her profession, Belle takes her to a sex club that specializes in peoples' fetishes, and the visit proves most enlightening---to both women. Elsewhere, Bambi has a first appointment with an aristocratic young man and finds herself quite attracted to him. And while battling writer's block, Belle seeks guidance from her editor, Duncan.

Business becomes pleasure when Duncan and Belle's editor-writer relationship takes a turn after a late-night chat about her next book. Elsewhere, Belle has difficulty accepting the affair between Jackie and Ben; and Bambi begins to have feelings for a handsome, young client, despite warnings from Belle about getting involved with her "dates."

Belle offers relationship advice to Ben as his romance with Jackie turns rocky, and Bambi, who is dating her client Byron. But when it comes to her own love life, Belle breaks all the rules she set for her friends.

Belle contemplates the possibility of a serious relationship with Duncan, but she has second thoughts when he refuses to acknowledge that they have been intimate. Meanwhile, Bambi's romance with Byron takes a major turn.

The initial meeting between Ben and Duncan is a bit rocky, leaving Belle with a serious decision to make.

To gain a more accurate understanding of the client-escort relationship, Belle hires a man's services for the evening, but begins to feel guilty about cheating on Duncan. The feeling doesn't last long, however, when she learns that her boyfriend spent some quality time with Bambi earlier that night.