Justin Bieber brought along a mystery date to Justin Timberlake's gig last night, leaving people asking, who’s that brunette Justin!?He was on his way to see another Justin, this time Timberlake, perform at The Forum, London, after his energetic performance at The Brits, where he marked his return to prominence with an excellent live version of Mirrors.

Bieber is in the U.K to fulfil the British leg of his tour, which kicked off in Ireland at 02 arena in Dublin. He wore his now infamous all white suit and the crowd couldn't seem to get enough of the Canadian hitmaker. He didn’t fancy heading to The Brits though, choosing instead to make a beeline for Kentish Town, where Timberlake was playing his one-off gig. He probably should have taken the time to see JT strut his stuff on The Brit’s stage, though, as it was certainly a night to remember for the freshly-returned star.

Justin Bieber Shows A Bit Of Shoulder

Justin Bieber Shows A Bit Of Shoulder at The O2 - Dublin, Ireland

Whoever the mystery date was, she clearly didn't get the attire-memo. Bieber was looking casual in jeans, his customary wacky trainers and a grey hoodie, while she glammed up in black, wearing a dress and a leather jacket. Justin was recently spotted partying with two women, taking them home. Rumours were that Justin was to meet up with his ex, Selena Gomez, but the presence of this mystery girl throws that out the picture, kind of. Furthermore, people have suggested the pair arrived together in Kentish Town, but made an effort not to be seen together. Doesn't sound particularly smart.