This week they return on Friday and Sunday at 8 p.m. to present their new folk-opera, Hundred Days, the story of a young couple who fall in love but have their time together cut short by illness. Their response is to live a condensed life of 60 years in the 100 days they have, moving through their twenties, thirties, sixties and eighties. It’s an enchanting concept, polished to a state of near perfection through workshops around the country, including one at the 2011 Cincinnati Fringe. $10. 8 p.m. Additional 8 p.m. showing Sunday Aug. 12. Know Theatre. 1120 Jackson St., Over-the-Rhine. 513-300-5669, knowtheatre.com.