4 September 2013 Last updated at 23:23 GMT Help
Sweet, shy and nerdy - words usually used to describe characters played by Michael Cera.
The Canadian actor made his name in the critically adored TV series Arrested Development, and in films such as Superbad and Juno.
But a number of smaller, independent films are showing him playing against type, with less appealing characters.
Talking Movies' Tom Brook reports.