And yet there is something uncanny about the busy Sierra Leonean thoroughfare as imagined by British writer David Matthews and artist Paul Howard's video installation. The crowds of people stand stock still, arrested in the very moment of the day.

The camera singles out some people in their stasis: a group poised as if to push a broken-down car that bears the logo of an education department on its bonnet; a woman carrying her shopping in a bowl balanced on her head; knots of immobile police officers. It's hard to know whether Rush Hour is a tableau vivant or a demi-mort.

Spread across three giant screens in London's Museum in Docklands, Rush Hour is in fact both. The crowds (Matthews and Howard recruited their cast of hundreds with help from actors from Sierra Leone's leading theatre company, the Freetong Players) gradually shift from their frozen positions and life continues. A soundtrack beeps and buzzes with the sound of traffic, advertising jingles and clips from talk radio shows.

One of the latter strands is about slavery: a caller thinks that Britain and America should pay reparations to Africa; another points out that it was often Africans who sold their fellows to slavers; a third caller says, get busy and get rich - Sierra Leone should not look back.

Rush Hour's images have a simple poetry about them, but beneath this superficial elegance, complex currents run. It is a video as much about African identity as the links between London and Freetown, a city founded by former slaves. (The city's founders left London in 1787 from the Blackwell Stairs, close by the museum.) But it is also, unavoidably, about slavery and the legacy of the trade.

The warehouse that now houses the Docklands museum was constructed in 1802 and has links to the slave trade - ships from these wharves sailed to West Africa, collecting human cargo bound for Caribbean plantations before returning to London laden with sugar. Despite huge mineral wealth, Sierra Leone - the world's second-poorest nation, according to United Nations' indicators - is a precarious place; years of civil war have taken a toll.

Matthews and Howard offer no glib remedies for historical injustices. Instead they show something far stronger: the possibility of dynamic potential. The graceful images of the arrested Freetowners are there to be undone: these people feature in order to be set free.

And in a deed that has a necessary symmetry to the East End's links to the slave trade, the Museum in Docklands opens in November London's only permanent gallery devoted to the slave trade entitled London, Sugar and Slavery. Both this and Rush Hour are fitting actions.

Louise Gray is a freelance arts journalist

Rush Hour is at the Museum in Docklands, London, until 1 November www.museumindocklands.org.uk/