Sandbox Theatre Project’s site-specific comedy features eccentric characters, over-the-top scenarios, and everyday gym members going through their daily routines. Written by director Justin D.M. Palmer and actors Cliff Chamberlain and Chelsea Cutler, the show makes a pertinent point about our insularity even in social environments. Brightly funny, Can You Spot Me? also exploits the comic opportunities of its fitness club venue: the small playing space means that audiences watch some of the action in the gym mirrors, but this adds a realistic touch. The company crams more than a dozen clever characters, and even an amusingly choreographed alt-rock anthem, into its hour-long silly, smart, agreeably sweaty show. Through 6/25: Sat-Sun 9 PM, Webster Fitness Club, 957 W. Webster, 773-456-2329, $15.