(above) The 1895 version, first seen by Sotheby’s specialists in a warehouse in Oslo.

NEW YORK - Several years ago, while manning a pre-sale exhibition for one of our London auctions, I was summoned for a secret mission along with my colleagues Philip Hook, Stephane Connery and Simon Shaw. The four of us slipped out of the building (to avoid suspicion, we didn't walk out together through the main entrance, but rather used the back door), and headed to Heathrow for the next available flight to Oslo. After landing we were met by an unmarked black sedan and driven to a warehouse located on the outskirts of town. Our purpose was to see the only version of Edvard Munch’s famous Scream in private hands. The pastel had been in the same family since 1937, and the present owner, Petter Olsen, had been in an exclusive dialogue with Sotheby’s for some time about the possibility of bringing the work to auction. The next step in this deliberative, and highly secretive, process was for the work to be studied firsthand by several Sotheby’s specialists. That’s where we came in.

The Munch Museum has both the first version (at left, from 1893) and the last (from 1910).

We signed in at the guard's station, were buzzed through a double set of doors and escorted to a cold, bare room with a single fluorescent light and one table pushed against the center of the longest wall. We waited. A few minutes later, two men carried in a large, reinforced box. Automatic screw drivers spun with a grinding sound, one by one pulling up each screw. The lid was opened, the protective paper pulled aside and there before us was the most familiar image in the world -- yet it was a shocking surprise to us. Before the endlessly referenced, infinitely disseminated image of angst and existential drama (a 20th-century notion which Munch felt and expressed decades in advance), we were struck by the work's chromatic brilliance. The blazing red-orange and lemon-yellow currents of pastel streaming across the sky, set against the near lapis blues and verdant green of the harbor and landscape, led us to a surprisingly joyous round of exclamations. A work that expressed misery was also a work of dazzling color. The Art Nouveau-inspired, sinuous curves of the land and sky were set against the sharply straight and rushing diagonals of the walkway. This horizontal plane was drawn as a plummeting diagonal, rushing down beneath the figure, making it impossible for the subject (what kind of being is it?) to ever traverse.

The Prime Version, from 1893, in the National Gallery.

The work was sealed and we were led out. Throughout the viewing we had all maintained a veneer of studied reserve, but as soon as we left the building, we burst into a frenzy of excitement, talking over each other about the picture, its status as an icon, and, of course, its potential value. This would be the stuff of auction history. The car awaited, but before heading to the airport to catch our plane back to London, we made a mad dash to both the National Gallery and the Munch Museum in order to compare the work we had just seen to the three other versions of The Scream before that initial startling viewing receded. First the Munch Museum. The earliest version, from 1893, read like the study it has long been thought to be: more summarily executed, limited in color and lacking the details of the pastel we had just seen. The 1910 version was a late reprise; the movement of the landscape and sky were nearly psychedelic. The figure appeared to be on the verge of melting, with greater shadows and hollows in the face; this is the only version in which there are no dark spots denoting the eyes -- it is nearly blind. Instead of the beady black irises, there are just the edges of the bony sockets. Neither work seemed to have the power and impact of the pastel.

Finally the National Gallery version, also from 1893, the one that Munch placed in the great Frieze of Life. It was larger, darker and more terrifying than the two in the Munch Museum. It exudes the force of Munch's singular vision, which he translated into a universal image of the human condition, without place or time constraining it. The impact was intense: in one compressed afternoon, we had seen all four versions of arguably the most famous image in art history after the Mona Lisa. (For me, the experience of viewing The Scream couldn’t have been more different from seeing the Mona Lisa. At the Louvre, standing among rows of visitors and looking up at Leonardo’s paintings behind its protective glass case, has always been a disappointment. In Oslo, the direct experience with Munch’s masterpiece – in the warehouse, and in both museums – was much more powerful than any number of reproductions could prepare us for.)

Whenever I travel I am always in a state of low-level anxiety over missing a plane, and I was very eager to get back to the airport. Stephane, one of my closest friends, is far more nonchalant. He kept slowing up to see the other treasures at the National Gallery, insisting there was no rush while I furiously whispered we were going to be late. Somehow we made it to the airport with plenty of time (a surprise to no one but me), and we were able to enjoy a few plates of wonderful smoked salmon with lemon and brown bread. At least one of us downed a shot of cold vodka.

Over the next few years, Phillip and Simon continued the dialogue with Petter Olsen, who, like his father Thomas before him, is one of the great collectors and custodians of Munch's legacy. A few months ago, Mr. Olsen decided to place the work for sale at auction, and plans to use the funds to create a new museum devoted to the artist. It will be offered in New York as part of the May 2 Evening Sale of Impressionist and Modern Art. For all of us, this will be one of the most memorable experiences we will ever have.