Next week, on May 11, Christie’s New York will sell ’s 1955 masterpiece Les Femmes d’Alger (Version “O”). The work appears set to become the most expensive painting ever to sell at auction, nudging aside the current record holder, Francis Bacon’s triptych Three Studies of Lucian Freud, which fetched $142 million in 2013.

There are less than 100 collectors worldwide who could purchase the piece, which already has the highest presale estimate ever for a painting at auction ($140 million). Nonetheless, the auction house expects a vigorous bidding war for the lot, similar to that of Picasso’s Nude, Green Leaves and Bust (1932), which in 2010 realized $106.5 million, the artist’s current auction record.

But the question on many minds outside the auction world’s inner circle is: What makes a painting like Les Femmes d’Alger (Version “O”) so darn expensive?

For three months that began in December of 1954, Picasso worked on a series of 15 canvases depicting a harem scene based on Eugene Delacroix’s Les femmes d’Alger (1834), a painting he had been fascinated with ever since he came to Paris as a young man to admire it in the Louvre. The series, also titled “Les femmes d’Alger,” was created to honor his recently deceased friend (and rival) Henri Matisse, who had been greatly influenced by Delacroix. With his own version of the harem scene, Picasso wanted to carry Matisse’s legacy forward and reflect on the works of earlier artists who had been inspired by Delacroix’s painting. As Picasso told his close friend Hélène Parmelin, “I have a feeling that Delacroix, Giotto, Tintoretto, El Greco, and the rest, as well as all the modern painters, the good and the bad, the abstract and the non-abstract, are all standing behind me watching me at work.”

Simply put, Les femmes d’Alger, (Version “O”) is the most significant Picasso from the latter half of his career that is still privately owned—and thus able to be purchased. As Brooke Lampley, international director of Christie’s Impressionist and modern department, told Artsy, “Of the 15 works dedicated to this subject, this is the most fully realized, detailed, and compact one.” It comprises all the influences present throughout his career in one canvas. Resplendent with colors and textures, it perfectly synthesizes Picasso’s formal experiments from the early part of his career with the attraction to sensual female forms that dominates the latter portion of his oeuvre.

All this has led the painting to accumulate an enviable lineup of museum appearances in Picasso retrospectives across the globe—among them, New York’s Museum of Modern Art in 1957 and 1980, London’s National Gallery in 1960, Paris’s Grand Palais from 1966 to 1967, and New York’s Metropolitan Museum of Art in 1968. In more recent accolades, Les femmes d’Alger (Version “O”) was included in the Louvre’s “Picasso et les Maîtres” survey, which opened in 2008, made a reappearance at London’s National Gallery in 2009 for “Picasso: Challenging the Past,” and hung in the Tate Britain’s exhibition “Picasso & Modern British Art” in 2012.

In 1956, Daniel-Henry Kahnweiler, Picasso’s longtime dealer, sold the entire series of 15 paintings, “Les femmes d’Alger,” to American collectors Victor and Sally Ganz for a total of $212,500. Ganz was the president of D. Lisner & Company, a small costume jewelry manufacturer, who with limited resources but a very good eye, built with his wife one of the world’s most important collections of 20th-century art. He bought his first Picasso, Le Rêve, in 1941 for just $7,000. (The painting later made the news when its subsequent owner, casino magnate Steve Wynn, inadvertently poked a six-inch hole in the picture with his elbow before selling it to hedge-fund manager Steven A. Cohen for a reported $155 million in a private sale in 2013.)

After the Ganzes respective deaths, their collection was sold at Christie’s in 1997 for a total of $206.5 million, shattering existing auction records for a single-owner sale. On that occasion, Les femmes d’Alger (Version “O”) was won for $31,902,500, double its estimate of $12 million. It hasn’t hit the market since.

With the market for modern art very strong once again, Picasso is one of the period’s best-selling artists. In terms of annual turnover, he was the most profitable artist at auction 17 times between 1989 and 2011. In the years since, he has been among the top-five selling artists in the West, with a total annual auction revenue in the realm of $300 million per year. His prices rose precipitously following the sale of Boy with a Pipe (1905), which fetched $104,168,000 at Sotheby’s New York in 2004, with exceptional values now routinely being reached, such as the $95.2 million paid for Dora Maar with Cat (1941) at Sotheby’s New York in 2006.

Picasso’s masterpieces are now in short supply and therefore getting increasingly expensive. This is especially true for paintings from his “Blue” and “Rose” periods, early Cubist works, and pieces that are intimately linked to the artist’s private life. The scarcity of works from his early years has had the knock-on effect of also raising the desirability (and, in turn, the price) of his later output as well. In recent decades, several important exhibitions have been dedicated to the final years of Picasso’s career, bringing greater understanding and recognition to his works from the 1950s. Ultimately, however, what many global collectors are seeking is the very best piece from any of Picasso’s periods, and Les Femmes d’Alger (Version “O”) certainly is one.