As they've done before — with Side Show, Grey Gardens, and Passion — Queen City Theatre Company is journeying beyond a musical comfort zone with Next to Normal. The 2010 Pulitzer Prize winner for drama boasts a probing script and lyrics by Brian Yorkey fused with a corrosive rock score by Tom Kitt. It's the musical Stephen Sondheim might have written if he'd dropped acid and been committed to an asylum. Alyson Lowe stars as Diana (the bipolar role that won Alice Ripley a Tony Award), desperately — sometimes comically — navigating her way through the wacky mental health system while trying to exorcise the memory of her lost son. Yorkey's script is no less empathetic to the other shell-shocked survivors, and with Billy Ensley, Abby Corrigan, and Matt Carlson in the cast, it should be an exciting ride. Glenn T. Griffin directs.