The Shakespeare Theatre Company presents this year's 20th annual "Free for All" production with 22 performances of Twelfth Night, more than double last year's number. Queer as Folk's Randy Harrison (and this week's Metro Weekly cover story), plays Sebastian as part of a cast that also includes Gregory Wooddell, Floyd King, Tom Story and Nancy Robinette. Alan Paul, who most recently gave us Signature Theatre's production of I Am My Own Wife, directs. Opens Thursday, Aug. 19, at 8 p.m. To Sept. 5. Harman Center for the Arts, 610 F St. NW. Tickets are free, distributed this year through an online lottery system, held daily. Call 202- 202.608.6350 or visit shakespearetheatre.org.