Justin Bieber was spotted out and about in London wearing a bizarre gas mask.
Bieber had dinner at upscale restaurant Mr. Chow in Knightsbridge before heading to 45 Park Lane hotel to hang out with friends and his entourage.
It's not the first time the singer has been the man behind the mask -- he baffled onlookers when he donned the creepy plastic and rubber gas mask last month.
Bieber turned 19 last week and tweeted that it was the "worst birthday ever" after being turned away from Cirque du Soir nightclub because his group included several underage teens, including Will and Jada Pinkett Smith's 14-year-old son, Jaden Smith.
He then kept fans at his concert Monday night at London's O2 waiting more than an hour past the scheduled start time before he took the stage.
Bieber's troubles didn't begin in 2013 however. He ended 2012 amid an outrage over photos of the singer allegedly smoking pot at several parties.
See Justin Bieber gas mask photos below.
photos: Craig Harris/WENN