Inspired by events hundreds of years ago and, tragically, more recent incidents, Ghosts is an immersive theatre experience delivered via an app from National Theatre Scotland. The immersive element is an augmented reality feature that shows users various images, maps, and videos as they follow a walking route through Glasgow’s Merchant City. Rather than a lighthearted game, though, writer and director Adura Onashile‘s creation is a poetic series of monologues thrusting listeners into Glasgow’s historical slave trade.

Beginning at Ramshorn Kirk, heavy breathing and a young man’s voice lead us into the journey. It’s clear from the opening lines that this is far from a typical guided tour. Rather than timelines, statistics, and chronological facts, Ghosts is an emotional exploration of individual experiences from 500 years ago. This is captivating at times and the actors orate powerfully. One monologue in particular – that of a pregnant woman on board a slave ship – is especially atmospheric and devastating, with simple but engaging accompanying visuals. A little context might be more helpful at times, though. The links between the buildings we’re encouraged to look at and the narrative we listen to are also unclear for most of the duration. Presumably they were either sites of slave trading or were built from the profits of that cruelty. More explicit information about this would be rewarding.

As well as the script, the soundscape has been carefully built and is, in fact, usually more immersive than the AR technology. In one location we hear distant voices in crowds, winds blowing and the crackle of burning crops, all working together to rise to a jostling cacophony. The visuals are more varied in effectiveness. Sometimes we are provided with fascinating photographs and CGI; in other spots we merely catch orbs of light or a slowly spreading 2D map of the city centre. Getting to grips with the app itself is relatively straightforward, although Android users may have a little more calibration-setting to do from stop to stop. The suggestion to begin with a full battery should also be taken on board, and trying to take part during the day with bright weather is a non-starter.

As a fully-rounded experience, the app feels a little uneven and lacking in parts. Ghosts is effective in shedding light on Glasgow’s slave trade, though – something that is ignored and buried too often. It also brings humanity to the forgotten voices and reminds us of what a huge part of Glasgow’s economy and architecture was borne from.