Why one major 'Stranger Things' star was missing at the Season 2 premiere this week

One Stranger Things star was notably absent from Thursday's Season 2 premiere in Los Angeles.

British actor Charlie Heaton, who plays creepy photo stalker man Jonathan Byers in the Netflix series, was barred entry to the U.S. last Saturday.

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The reason? A drug-sniffing dog reportedly picked up on something that prompted a search of Heaton's luggage, at which point authorities discovered "a small amount of cocaine," according to the Associated Press.

Heaton was neither arrested nor charged, but he was barred from entering the U.S. and promptly sent back to London. It's worth noting here that the AP's report comes via an anonymous source — an official who "couldn't discuss the matter publicly."

A Friday night report from People contains the same information, via an unnamed law enforcement source. That story also includes a vague statement from U.S. Customs and Border Protection which lays out the federal agency's rules for handling foreign nationals in violation of controlled substance laws.

It read: "A violation, conspiracy to violate or simply an attempt to violate any U.S. State, federal or any foreign government controlled substance violation renders a foreign national inadmissible to the United States."

Heaton hasn't yet made any public statements on the matter, though this would explain his absence from Thursday's premiere.

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