Here is a fine new Australian opera from Victorian Opera. Composer Iain Grandage and librettist Alison Croggon have taken Tim Winton’s Booker-shortlisted novel The Riders (1994) and created a highly expressive work. Marion Potts directs it on a wide but stark stage furnished only with wooden saw horses. There is a balcony and a revolve, but mostly Potts chooses to observe her anguished and introspective characters through a series of fairly static groupings.