A gullible character named James Lingk is fast-talked into making a purchase by Ricky Roma, and in the end Shelly Levene is nabbed for robbing the sales leads.  
One character in this work chides his manager with "you are a shithead" after another character chews out that manager by claiming "a child" would know that "You never open your mouth until you know what the shot is."  A plot to defect to Jerry Graff is hatched by Dave Moss, who first attempts to recruit Aaronow but whose eventual accomplice is nicknamed "The Machine."  A gullible character named James Lingk is fast-talked into making a purchase by Ricky Roma, and in the end Shelly Levene is nabbed for robbing the sales leads.  For 10 points, name this drama about Chicago real estate agents, by David Mamet.
One character in this work chides his manager with "you are a shithead" after another character chews out that manager by claiming "a child" would know that "You never open your mouth until you know what the shot is."  
{Glengarry Glen Ross}