Toronto police are investigating an art theft from the Banksy exhibit that is in Toronto for a month.
Banksy is a world famous and anonymous British street artist who uses graffiti as a form of activism.
One of the prints that was to be put on display was stolen over the weekend.
It is called Trolley Hunters and police say it has a value of $45,000.
"I am wholly dismayed to hear that this work was stolen," says Ryland Behrens, founder of the Hexagon gallery in California.
The print shows cavemen holding weapons towards a bunch of shopping carts.
"My interpretation of that work is a very sardonic or sarcastic look at the imposing nature of consumerism in society," Behrens says.
"It is a truly iconic work from the mid-2000s."
Police have not released any further information about their investigation.
Banksy