Authorities uncovered a secret heroin stash shop behind a fake door inside a Brooklyn candy shop Thursday, police said.

State Finance Department officers conducting an inspection for untaxed cigarettes found the secret door disguised as a shelf inside Gates Candy & Grocery in Bushwick Wednesday night.

They informed police, and cops raided the shop Thursday. They found boxes of drugs and packing material, including over 1 million glassine envelopes, Ziplock bags of what appears to heroin, two barrels of cutting agent and several blue bags of what police believe to be fentanyl, the NYPD confirmed.

Two men were taken into custody. Police told The Daily News the suspects were likely distributing drugs across Brooklyn and Queens.