Many fans arriving at the O2 in London for tonight's U2 show found themselves unexpectedly getting on a bus. But no one left the venue parking lot.

They were getting on something called "The Experience Bus," a (non-moving) partnership between U2 and Apple Music that invites fans to get on the bus and watch a new, virtual reality video of "Song For Someone." As you're watching the video, you get to interact with U2 as if you're standing on the e-stage as they perform. You also see other fans singing the song, too -- presumably sourced from several months ago when fans were invited to send the band videos of themselves singing the song.

While watching the video, fans have their photos taken and uploaded to a new website, U2TEB.com, where the fan can collect and/or share the image online. A couple of our staffers tried out the bus before tonight's show, including forum moderator Kenny Irwin ("singnomore" on the forum), who posted this photo of himself watching the "Song For Someone" video:

Inside the bus are a number of iPad displays, presumably where Apple Music is promoted. Upstairs on the bus are several booths that have the virtual reality glasses and Mac laptops setup to show the video.

The bus will be at some, but not all, of the remaining shows on the European tour. Our friend Heather Wallace did a live stream tonight, and one person working the bus said it'll be at the first two shows in London, all four shows in Paris and the last two shows in Dublin.