Using materials bought from Walmart or Walgreens, Mark Landis created fake works of art that he donated for decades to art museums across the country.

The art forger found his gift after he had a nervous breakdown and was diagnosed with schizophrenia as a teenager after his father died. Prescribed art therapy, he discovered he could forge pictures in virtually no time at all.

Even after his donations were found to be fake in 2008, after donating pictures for over 20 years, Landis did not have to face prosecution–he was never paid for his forgeries. He was finally caught by the museum registrar at the Oklahoma City Museum, Matt Leininger, after Leininger figured out what was going on.

“We received an envelope in the mail which had five additional works in,” Leininger told BBC. The paintings were allegedly by French 19th Century artists Paul Signac and Stanislas Lepine. Leininger added:

I did some research on the Signac, and it showed up in a press release by the Savannah College of Art and Design under the same credit line – Mark Landis. I didn’t think too much about it until I looked up the Lepine, and it showed up in a press release at the Saint Louis University of Modern Art – with the same credit line. That raised a red flag. I sent a message out, and within the first hour, between phone calls and emails I had 20 institutions call me and ask who this guy was and what was going on.

Landis began his career donating in the mid-1980s, giving pictures allegedly by the American 20th Century artist Maynard Dixon to a California museum. He recollected:

It was an impulse to impress my mother. I always admired the rich collectors on TV giving away pictures to museums … I put Maynard Dixon’s name on them because that’s what the museums wanted. He was a cowboy artist, so I went to the library and checked out some books of photographs of American Indians, and copied a bunch of them. I knew the museums wanted cowboy pictures, so that’s what I did.

After Leininger discovered that Landis was a fraud, he pulled apart a chalk drawing Landis had submitted as 300-400 years old. Leininger said he expected the drawing to be flimsy and fall apart, but it didn’t: “when I peeled it back it was stark white. And it smelled like stale coffee. So he was using coffee to distress things to give them age.”

Leininger surmised that Landis convinced curators to take his paintings because he was prepared, saying, “Landis would do his homework. He knew what museums collected. He was pretty sure they were going to be accepted because it would have fit their collection. He said everything an art museum would want to hear… a back story about how he had this art collection and supposedly family wealth, promising money for endowments.”

In 2012, the Cincinnati Art Museum exhibited creations by landis on April Fool’s day. Landis, invited to be the guest of honor, said, “I was really nervous before the show because I didn’t know what to expect. But then when I got there everything was really nice. So I was pleasantly surprised.”

Landis summed up why he did what he did: “It obviously isn’t a crime to give a picture to a museum, and they treated me like royalty. One thing led to another, and I kept doing it for 30 years. Have you ever been treated like royalty? Let me tell you, it’s pretty good.”