In advance of their upcoming tour with singer Adam Lambert, Queen took the stage in Southern California on June 16, delivering a warmup show to 400 fortunate fans that included the first-ever live performance of the Freddie Mercury solo track 'Love Kills.'

Taped for broadcast, the show -- which took place at the iHeartRadio Theater in Burbank -- included a few non-Queen celebrity appearances, including one from Motley Crue's Nikki Sixx, who served as host for the evening's festivities. The band's online tour diary made mention of Sixx's involvement, calling him a "great songwriter, an engaging radio host and huge music fan, plus, I must say that album that Motley did with John Corabi in 1994 just smokes, the best thing the Crue ever did to my ears."

The Queen/Sixx lovefest continued on Twitter, where the band thanked him and he offered followers a behind-the-scenes shot of the action. Also on hand: Kiss guitarist Tommy Thayer, who posted a picture of himself backstage with guitarist Brian May.

Those in attendance witnessed an eight-song set that, aside from the live debut of 'Love Kills' also included performances of 'We Will Rock You,' 'Another One Bites The Dust,' 'Crazy Little Thing Called Love,' 'Love Kills,' 'Fat Bottomed Girls,' 'Under Pressure, 'We Are the Champions,' and 'Don't Stop Me Now.' Keep an eye out for more surprises once Queen's tour starts in earnest on June 19.

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