I have converted people to opera with TOSCA: three relatively short, highly dramatic, "wham, bang, thank you, ma'am" acts. A masterpiece! It never fails. Personally, I love Wagner and Richard Strauss, but I wouldn't suggest anyone new to opera started with either of them. A less well-known Puccini opera is the one-act IL TABARRO - that's wonderfully, darkly dramatic (and, of course, melodic too). Another great favourite of mine is Berlioz' THE TROJANS - but that is very long. For terrific tunes, raw emotion and drama, and a perfectly shaped plot and score you'd have to go a long way to beat Bizet's CARMEN. I've sung in three different productions, the last one with the Royal Opera House, Covent Garden, and I marvel at the sheer dramatic genius of the work more and more each time I encounter it.