. >> reporter: many opera fans consider maria callas one of the greatest opera fans whoever live.n she died the fans were heartbroken. so they might be shocked to learn that maria callas is going on tour this spring, complete with a live 60-piece orchestra. ♪ >> her return is brought to you by hologram, or what is being called a hologram. >> we are presenting them to audiences to either see them again or audiences that have never seen them before. >> brian becker is the ceo of base entertainment, which created the maria callas show. >> most of us think of a hologram as a futuristic projection. like princess leia, you could walk all the way around her, see her from the back. that is not what we are talking about. >> this is a 3d illusion, but holographic technology is a good name that people recognize. >> she's hardly the first dead musician to take the stage again. the first example was at the coacella music festival when rapper tupac rose from the dead. the technology for that stunt is now owned by a company called hologram usa. >> no stranger to controversy. at his theater on ho