NEW YORK (CNNMoney.com) -- A new ad campaign launched by the owner of the M&M's brand aims to make eating dark chocolate a scream.

M&M's is offering 2 million dark chocolate M&M's for the return of "The Scream," a painting by Edvard Munch that was stolen from the Munch Museum in Oslo, Norway, in 2004.

The campaign accompanies the permanent addition of dark chocolate candies to the M&M's product line, which was announced earlier this month.

"We've received tremendous interest from consumers to make M&M's Dark Chocolate a permanent offering," Michele Kessler, vice president of marketing at Masterfoods USA, said in a statement.

Masterfoods USA owns the M&M's brand and is a part of closely held food manufacturer Mars, Inc.

The campaign aims to bring some fun into the dark chocolate category, which is perceived to be more serious, Masterfoods said.

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