Bolshoi's Sergei Filin back at theatre after acid attack Artistic director of the Bolshoi ballet Sergei Filin, left, speaks to the media after a traditional annual meeting of the Bolshoi Theatre in Moscow, Russia. THE Bolshoi ballet's artistic director has returned to the famed Moscow theatre after months of treatment following an acid attack. The January attack on Sergei Filin exposed a fierce power struggle within the theatre. The general director and his rival, a principal dancer, were both ousted in the aftermath. Filin appeared on Tuesday for the ballet company's traditional gathering to kick off the new season, but said he was not yet ready to resume work and would be travelling back and forth to Germany for continued treatment. Filin wore tinted eyeglasses, not the dark shades of months past. His vision was reported to be 80 per cent restored in his left eye, but to remain poor in the right due the acid that was thrown at his face.