Grateful Dead members Bob Weir, Mickey Hart, and Bill Kreutzmann will be starting a new project called Dead & Company with John Mayer joining them. The new group will be debuting the project on Halloween at Madison Square Garden. Phil Lesh, the Grateful Dead’s bassist, will not be taking part in the group, with the band being rounded out by Oteil Burbridge (the Allman Brothers) and Ratdog keyboard player Jeff Chementi.