Two of the plays in Pegasus Players’ 20th annual showcase are surprising and textured. The strength of Mikal McLendon’s Writing Your Tragedy, directed by Tiffany Trent, is the very real, very raw dialogue among siblings who react to their father’s death by pulling further apart. And Brian Tasch’s An Evening With the Living Dead, directed by Alex Levy, is a spot-on Scream-style zombie parody with a wise undercurrent of social commentary. But the third, written by 13 high school students, is bloated and derivative: the team from Our Lady of Tepeyac falls short with I Am Someone, directed by Michael Myers, providing only familiar monologues about gangs, abortions, and teenage alienation. Through 1/29: Fri-Sat 8 PM, Sun 3 PM, Pegasus Players, O’Rourke Performing Arts Center, Truman College, 1145 W. Wilson, 773-878-9761, $12.