The Mercury is a producing theatre on Balkerne Hill, founded in 1972 and recently rebuilt with a striking new foyer extension. Its productions — typically four or five a season, mixing classics, new writing, and a Christmas show — have a regional reputation that punches well above the town's size, and several have transferred to London.
The bar and cafe stay open most days even when no show is on; on a wet afternoon they are one of the more comfortable places to read in the town centre. Worth checking the website before you visit — a midweek matinee can be a useful refuge from a flat day in Colchester's main shopping streets.