Paintings by a Canadian artist who killed himself at age 35 in October are setting records this auction season.

At his New York solo debut two years ago, Matthew Wong's new works sold for $22,000. When one of those canvases returned to the market Monday at Sotheby's, it fetched $1.5 million excluding fees, with 59 registered bidders from 16 countries in pursuit. The seller was former Sotheby's executive Allan Schwartzman, according to people familiar with the matter.

More works are hitting the block: Phillips will offer a painting and a watercolor by Wong on Thursday at its marquee auctions in New York, and another painting next week in Hong Kong.

Wong's career was just taking off at the time of his death, with another solo show a month away and the billionaire Lauder family among his burgeoning collector base. The demand for his melancholy landscapes, often with a tiny, solitary human figure, has only grown since. While his show at Karma in New York proceeded as planned in November, no works were released for sale, according to Brendan Dugan, the owner of the gallery that represents the Wong estate.

"I had been hunting for a painting," said David Galperin, head of Sotheby's contemporary art evening sales in New York, who secured "The Realm of Appearances" for the auction. "At least on the primary market, Wongs have been nearly impossible to obtain."

Collectors have been fielding offers to sell for as much as $300,000, according to Lisa Schiff, an art adviser who placed 11 pieces with five clients early on. In May, a 2018 watercolor fetched $62,500 at Sotheby's, up from less than $5,000 two year ago.

"Remarkable things have been happening around his work," Dugan said. Universal yet personal and evocative of traditional styles such as Chinese ink painting and Impressionism, his pieces have drawn strong reactions from the start. "There was the urgency for him to create," he said. "That's where the power comes from."

Born in Canada, Wong grew up in Hong Kong, studied photography and began painting in his late 20s, without formal training. In recent years he lived with his parents in Edmonton, Alberta, corresponding with critics and dealers on Facebook and visiting fairs in Basel and Los Angeles.

His mother, Monita Wong, told the New York Times in October that her son was on the autism spectrum, had Tourette syndrome and had grappled with depression since childhood.

Wong was prolific, completing paintings in two or three days, said Dugan, who's working on Wong's catalogue raisonne. He created about 1,000 works in his lifetime.

Dugan met the artist in 2016 through curator Matthew Higgs, who included Wong in a group exhibition -- "Outside" -- of landscape paintings by outsider artists at Karma in the Hamptons. Two years later, the gallery gave Wong a solo show in New York. Jerry Saltz, a Pulitzer Prize-winning critic for New York magazine, called it "one of the most impressive solo New York debuts I've seen in a while."

"The Realm of Appearances," which depicts a richly patterned, jewel-toned meadow beneath a steel-gray night sky, was a centerpiece of the exhibition. In its auction catalog, Sotheby's drew parallels between the landscape and works of Vincent van Gogh and Edvard Munch.

Estimated at $60,000 to $80,000, the lot drew frenzied bidding from collectors in the U.S., Europe and Asia. All of the phone lines were jammed. Bids climbed to $500,000 within seconds -- and kept going until the hammer fell at $1.5 million, resulting in a return of about 6,700% for Schwartzman, a prominent art adviser who left Sotheby's this year.

He didn't reply to messages seeking comment.