LONDON — Christie’s has announced what is likely to be the main highlight of its February contemporary art evening sale: a triptych by the British artist Francis Bacon (1909–92). “Triptych 1974–77,” estimated at $50 million, was painted in reaction to the drug overdose and death of Bacon’s lover George Dyer in 1971, and was completed in time to appear in Bacon’s show at the Metropolitan Museum of Art in 1975. The work is sinister and remote — three images of dyer struggling with an umbrella on a beach, with two monstrous faces glaring down at him in the central panel. Yet in typical Baconian style, it is gorgeous, too, with swirls, smudges, and swaths of blues, purples, browns, and black. The psychological torment of the artist is perhaps apparent in the extensiveness of the dirty brown sand, which calls to mind illness and unrest and pushes away any ideas of beauty and peace.

“Triptych 1974–77” has never been sold at auction before, and is expected to outshine the artist’s performance at the October contemporary art sales. Then, Bacon’s much-hyped “Study from the Human Body, Man Turning on the Light” went for a mere £8 million (about $16 million). In February 2007, his “Study for a Portrait 2” went for $28 million. The world record for a Bacon painting stands at $52,680,000 for “Study from Innocent X, 1962,” sold at Sotheby’s New York in May 2007.

Of course, Sotheby’s will match Christie’s with a high-profile Bacon of its own for its February evening sale of contemporary art. “Study of a Nude with Figure in a Mirror” is an animalistic rendering of his close friend Henrietta Moraes, showing a grizzled, expressionless man peering out at her from under a top hat in a mirror, and is estimated at about $36–$50 million.

For the first time, however, Sotheby’s and Christie’s will not hold their sales in the same week. Just before Christmas, Sotheby’s announced a breakaway contemporary art week, with its evening sale on February 27, several weeks after the Impressionist sales. Normally, both houses hold contemporary and Impressionist sales in the same week. Sotheby’s says it decided to separate the sales in light of the growth in the contemporary art sector, namely a 348% rise in the value of London sales between 2001 and 2006. The number of lots sold annually in London has doubled since 2002, Sotheby’s said.

Whether or not the buzz next month will match that of the October sales is unclear; then, Frieze, Pulse, and various other art fairs were taking place. The champagne was practically running in the streets, and the clip-clop of Manolo Blahnik heels was deafening. But perhaps all that isn’t necessary for the wallets to come out.