“You could forgive Kurt Beattie for being a bit blasé on the eve of ACT Theatre’s 2007 season, which opens with the Seattle debut of Sarah Ruhl’s touted play ‘The Clean House.’ But ACT’s respected artistic head is anything but jaded. Since he was diagnosed with lung cancer late last year, Beattie has endured aggressive treatment. And he’s very happy to be alive — and back to work.”