Famed for setting complex and unlikely texts to music, Pulitzer-winning composer Dominick Argento has plumbed the depths of Virginia Woolf's diary, and combined Chekhov's one act On the Harmful Effects of Tobacco with passages from the Audubon's Birds of America, but his first international success was based on the seemingly innocent collection of children's verse by Robert Louis Stevenson. This slightly surreal, decidedly existential one-act opera is set in an outdoor train station where passengers must pass the time before leaving for an unnamed exotic locale. In the honored practice of American opera, Postcards From Morocco is not bound by a concrete narrative (or even real language for that matter), it offers instead a series of powerful images and implications as characters reveal their lives through what's hidden in their baggage. As Argento runs the gamut from Wagner to ragtime, his characters slowly devolve into paranoia, bitterness, and bullying. In this production, Portland Opera's stage director Kevin Newbury eschews puppetry and costume changes for the more serious questions raised between shrieks of the train whistle.