Pacino movie films in middle of concert by Chicago

Pacino returned to the stage during Chicago's encore and sang and danced.
LOS ANGELES (AP) - An Al Pacino movie broke out in the middle of a concert by the band Chicago, with thousands of fans serving as extras.
Cameras were wheeled onstage during intermission of the group s show at the Greek Theatre on Friday night to film a scene from Pacino s upcoming movie "Imagine," in which he plays aging rock star Danny Collins.
With coaching from the director, the crowd chanted the name of Pacino s character as the 73-year-old actor walked on stage to sing "Hey Baby Doll" in a black suit. The movie co-stars Michael Caine, Annette Bening and Jennifer Garner.
"This is an improvisation," Pacino told the crowd. "You just came in and got it. That s not easy."
Chicago s band members remained on stage to watch and clap along during the 25-minute filming. After a few takes, the crowd grew restless and there was scattered booing for the real musicians to resume playing.
Earlier in Chicago s set, Joe Mantegna of CBS "Criminal Minds" joined his hometown band to sing "If You Leave Me Now."
Pacino returned to the stage during Chicago s encore and sang and danced to their hit "25 or 6 to 4."
"For a shy guy from the South Bronx, this has been great," Pacino said.