Has the Francis Bacon cult peaked? For most of the second half of the 20th century, the Irish-born painter’s unstinting bleakness, ravaged flesh and sado-masochistic homoeroticism made him the outrage king of British art. Think Damien Hirst to the power of 10. The very mention of Bacon’s name induced a shiver up the spine, among fans as much as detractors.

If the 21st century brought Bacon retrospective acclaim as the greatest British artist of his time, it also gave him perhaps too much acceptance and familiarity. Thirty-two years on from Bacon’s death, this major exhibition featuring 58 paintings is an opportunity to assess if the artist described by Margaret Thatcher as “the man who does those dreadful pictures” is still a unique figure, who hits us on levels other artists don’t reach. Bacon on the face of it is a no-brainer for the National Portrait Gallery .

Just about everything he did was to some extent a portrait. Yet besides the symbolic depictions that made him famous – the notorious screaming popes and sinister images of anonymous, besuited men – there are many portraits of actual people. The news that the NPG’s show groups its exhibits around particular individuals who sat regularly for Bacon and with whom he remained preoccupied for decades – including Lucian Freud, Soho’s Colony Room proprietor Muriel Belcher, and his petty criminal lover George Dyer – suggests we could be in for a rather gossipy, lightweight show.

Such an exhibition woul.