Bond girl, fashion icon, renowned stage actor, Gurkha champion: Joanna Lumley has had a wonderful career. But it is her portrayal of Patsy in Absolutely Fabulous that is stamped on the nation's consciousness. She talks about the new episodes of the show

By Stuart Jeffries: We're meeting because Lumley is starring in three new episodes of Absolutely Fabulous, in which she plays ageless, deathless, creaseless but never drugless, fagless or boozeless Patsy Stone. It's 19 years since we first saw her as Patsy and seven since the sitcom was last broadcast. Two episodes will be shown over Christmas, and the other sometime in the new year.

Lumley's BBC minder has warned me not to blab the identity of one guest star or detail a shocking storyline. So all I can say is that I was surprised that Ab Fab isn't yet Obsoletely Fatuous. Although the humour is sometimes insufferably broad, co-star and writer Jennifer Saunders' scripts are sharper than ever.

There is even loose talk about an Ab Fab film. True? "Well, Jennifer said so, on the Graham Norton show. It's entirely up to her. But sometimes she will say things like this in order to spur herself to write." If it happens, would you want to play Patsy? Lumley emits one of those faux-plebby porcine snorts that Patsy gives when Eddie's said something funny. By which Lumley means, surely, that she would produce a revolver from a stocking top and shoot anyone who stood in her way of that film role repeatedly and deservedly in the face. "It's got to be all the Js together," she says, meaning: Jennifer Saunders (Edina Monsoon), Julia Sawalha (her daughter), June Whitfield (Edina's mother) and Jane Horrocks (Edina's assistant Bubble).

In any case, who else could play Patsy? Perhaps only Meryl Streep and even then Streep could hardly do justice to some of the new lines Saunders has written for her, such as Patsy's comment on the riots: "Nothing wrong with a bit of extreme shopping"; or her sneer when someone suggests she take fewer drugs: "Have you seen the price of methadone? Cheaper to buy crack."

The role of Eurydice Colette Clytemnestra Dido Bathsheba Rabelais Patricia Cocteau Stone, aka Patsy, is, lest we forget, substantially Lumley's creation. Ab Fab is the mutant offspring of a French and Saunders sketch about an ageing alcoholic, drug-abusing PR agent desperately trying to stay fashionable (and in part modelled on fashion PR Lynne Franks) and her strait-laced, speccy bookworm of a schoolgirl daughter. There was initially no Patsy. Where did she come in? "Patsy sprang fully-formed like Medusa from the head of whoever it was." Zeus. But that's not quite right: Patsy was initially stillborn. When, in the early 1990s, Lumley turned up for a read-through of a scene for the AbFab pilot, she couldn't make the character sound the way Saunders was hoping for. As she recalls in her autobiography: "Jennifer can be very silent; on this occasion I felt so inadequate that I went back home, rang my agent and said: 'Get me out of this.'"

The agent, as you may have noticed, did not.