Blur was one of the last projects developed by the now-closed Activision studio Bizarre Creations, and some newly revealed prototype footage offers a look at what the team could have done in a sequel. Former Bizarre artist and Blur art director Chris Davie shared a pair of videos on his personal Tumblr that offer a look at the never-completed game (via Superannuation).
The two Blur 2 prototype videos offer looks at the planned gameplay as of 2010, with one set on Blur's Brighton Storm race track and the other set on a new track in Dubai. Note that much of what you see in the videos is built on "tech and assets" from Blur, with the studio using the earlier game as a foundation to try out some new tricks and visual effects.
It's a bit of a bummer to look at a game that will never be, but it's also a cool glimpse into the pre-production work that goes into creating a sequel.