Ririka (1934), part of the GNO’s Greek Operetta Cycle, was a lecture/presentation event at the Olympia Theatre Foyer (29 December 2013, free admission) about the operetta by Corfu-born composer Stathis Mastoras (1893-1943), with libretto by Yiannis Prineas. Though only one song survives in the public mind, the operetta was a smash-hit in its time, featuring powerful drama, poignant social criticism and hilarious characters. Mastoras, one of the sadly forgotten protagonists of the second generation of Greek operetta composers, was executed by the Nazis on Crete in the 1943 massacre of Viannos.