The duo join an ensemble which already includes Ben Affleck, Kevin Costner and Tommy Lee Jones. ER creator John Wells will make his big screen directorial debut with the project.
Company Men will tell the story of a corporate high-flyer (Affleck) who becomes a victim of recession. Losing his six-figure salary, Affleck's character goes to work for his brother-in-law (Costner) on a construction job.
Bello is cast as the head of human resources, who is forced to fire Affleck's character, while Nelson is playing the CEO of the firm.
Shooting has already begun in Boston.