Margin Call (out Mar 15) looks at 24 hours in the life of a major investment bank that is on the brink of collapse. Thankfully, the film does not demonise these characters - it portrays them as level-headed human beings who must decide whether to put their own interests ahead of others. The dialogue is superb and writer-director J.C. Chandor deserved his Oscar nomination for best original screenplay. Grade: A.