Concussion is based on the true story of Pittsburgh-based forensic pathologist DrBennet Omalu (played by Smith), who discovered a neuro-degenerative disease called chronic traumatic encephalopathy (CTE) after conducting an autopsy on a former NFL player.
Despite the film's serious subject matter - the danger of concussion in contact sport - Smith's attempt at Omalu's Nigerian accent has been largely ridiculed on social media.
The film has caused controversy for the NFL - Buzzfeed discovered a strategy for dealing with its release in the Sony email hack - and is being lauded as a potential Oscar contender.
But will audiences be able to get past Smith's terrible accent? The verdict on Twitter appears to be a resounding 'no'.