When Philip Roth told the French magazine Les Inrockuptibles in November 2012 that he was quitting the field – "To tell you the truth, I'm done" – there was widespread disbelief. Surely a novelist who had devoted himself as singlemindedly to his art as Roth could not be serious? Was it possible that Nemesis, his 24th novel, would be his last? Well, yes, it was.

This week, in a BBC interview, Roth will not only reaffirm his literary retirement, he will also, with gleeful finality, guarantee to the camera that "this is my last appearance on television, my absolutely last appearance on any stage anywhere".

Roth's last word that, quoting American heavyweight boxer Joe Louis, he had "done the best he could with what he had", has been typically smart and self-conscious. It's a good retirement. Literary lives often end badly with poor health, rejection and neglect and it's all about Roth – how could it not be? He has devoted his long and distinguished literary career to reinventing himself in countless teasing ways. Now, at 81, he continues to tantalise his audience.

On Tuesday the BBC will broadcast his "last interview", a valedictory two-part conversation with Alan Yentob, shot at his Manhattan home in a film for Imagine, directed by Sarah Aspinall.

This latest episode in Roth's long goodbye shows the novelist, whom some consider to be America's greatest living writer, in a mood of playful relaxation, conceding that, hitherto, he had not wanted to "talk, talk, talk, talk, talk". Now, he says, "now that I don't write, I just want to chatter away". Inevitably, with his eye on his readers, Roth's chatter is all about the polyvalent character of his career. He has lived many literary lives. First, there was the wunderkind author of Goodbye, Columbus (1959), a landmark postwar debut. Next came the enfant terrible of Portnoy's Complaint (1969), the late-60s comic sensation, dubbed "a wild blue shocker" by Life magazine. "I got literary fame," he recalls. "I got sexual fame and I also got mad man fame. I got hundreds of letters, 100 a week, some of them letters with pictures of girls in bikinis. I had lots of opportunity to ruin my life."

So then he began to retreat into a kind of rancour, and became the experimental satirist of Our Gang (1971) and The Breast (1972). Next, in young middle age, Roth continued the exploration of his turbulent self in My Life as a Man (1974) and The Professor of Desire (1977). Later, he nurtured a more secure literary alter ego in his Zuckerman novels. The best was to come. In 1997, in his mid-60s, Roth embarked on a sequence of novels, well-wrought reinventions of America's recent past, that were hailed by critics on both sides of the Atlantic. Here in American Pastoral, I Married a Communist, The Human Stain, The Dying Animal and The Plot Against America was a vigorous refutation of Fitzgerald's bitter aside that "there are no second acts in American lives".

No writer in living memory has had such an extraordinary late-season surge. Roth's own account of this switch from the personal to the public is that, as he puts it, "in the beginning, it's about [Roth] coming of age, developing as a writer. Then it's not about him. He's the ear, the voice, he's the observer, he's the eye." Before his retirement, Roth's mood became valedictory (Exit Ghost, 2007) but still defiant (Indignation, 2008).

He reports that, in old age, "the last thing I wanted to do was to make myself more visible then I already was. The visibility unnerved me. And so I moved to the country." Roth retreated to an isolated farmhouse in Connecticut. He describes, almost for the first time, the conditions under which he wrote the sequence of novels that followed American Pastoral. "I find it very congenial to live in the natural beauty of the place I have in Connecticut. I work during the day, do some exercise late in the day" – he swims regularly – "and so I haven't lost contact with what I've been doing all day."

This, for many years, was standing for hours at his writing desk, to spare his back, "day in and day out. Then if I'm stuck, and I often am stuck, I walk out the door and I'm in the woods. I walk around for 10 minutes, and I come back and try again." Roth quotes his own character, Zuckerman, to explain this monk-like dedication: "I believe that we should read only those books that bite and sting us. If a book we're reading does not rouse us with a blow to the head, then why read it ?"

In 1976, Roth moved to London to live with actress Claire Bloom. But he didn't feel at home. "I couldn't write a feature-length book about London," he says now. "England made a Jew of me in only eight weeks."Here, Roth's conversation covers much contentious territory, including the repeated accusations of the novelist's alleged misogyny. But one tantalising detail is omitted. According to Yentob, when Roth attended a 70th birthday party for conductor Leonard Bernstein, he was seated next to Ava Gardner, who had been living in seclusion in London for several years. Gardner, who had been married to Frank Sinatra, joked to Roth, "I used to go out with a boy from Hoboken", and the pair spent the evening in intense conversation. In the course of his interview with the BBC, Roth occasionally challenges Yentob with "Go on, ask me about Ava Gardner", but discretion appears to have prevailed.

"We will leave that to Blake Bailey [Roth's biographer]," says Yentob coyly.

Roth has never seemed so relaxed or content. Usually, a cocktail of vanity, optimism, and defiance, spiked with raw economic necessity, keeps old writers in the game long after they should have bowed out. Roth has beaten the odds. When challenged with his 2004 statement that he "could not conceive of a life without writing", he replies: "I was wrong. I had reached the end. There was nothing more for me to write about." With a flash of candour, he adds: "I was fearful that I'd have nothing to do. I was terrified in fact, but I knew there was no sense continuing. I was not going to get any better. And why get worse ? And so …

"I set out upon the great task of doing nothing. I've had a very good time over the last three or four years." Much of this has been devoted – in another reinvention – to assisting Bailey, who says he will complete his biography in 2022. To this, Roth jokes: "I'll do my best to stay alive 'til 2020, but don't push me. Now that I don't write, I just want to chatter away. Bye, bye."