National Theatre of Scotland, Glasgow GLASGOW’S Merchant City was built on profits from the slave trade and the same applies to Edinburgh, Bristol, Liverpool and other cities. It takes outstanding, innovative art to plant this historical truth in the imagination, bring us close to the human cost and touch us — and the National Theatre of Scotland’s production of Ghosts, written and directed by Adura Onashile, is a stellar example. In it, a young man in 18th-century Glasgow is the guide to a 500-plus years of resistance through the streets of the Merchant City down to the River Clyde.