British mystery writer Dashiell Hammett's The Glass Key is a story about murder, money, friendship, and deceit. Particularly, the novel demonstrates how money—perhaps above all else—can compromise both one's reputation and one's friendships.

Ned Beaumont's discovery of Taylor Henry's body goes unreported until he clears it with his friend Paul Madvig, a mob boss. In the novel's opening scene, Madvig gives Beaumont, the protagonist (who admits to having had a bad streak of gambling), a sizable sum of money, thus revealing Madvig's practical influence on Beaumont—as well as on, it is understood, many other racketeering types in New York City. Because Madvig is the purveyor of money to those who need it, he is able to wield such influence that his friend (Beaumont) is reluctant to call the police upon finding a dead body without consulting Madvig first.

Another illustration of the power of money in the novel is when Ned Beaumont comes into several thousand dollars by betting successfully on a horse race. Beaumont probably wouldn't care so much about Taylor Henry's murder were it not for the simple fact that Bernie Despain, the man in charge of paying Beaumont his winnings from the horse race, seems to be unable to pay him as a result of having been owed money by Taylor Henry (as there were several I.O.U. notes form Henry that Despain left before allegedly leaving town). Beaumont is even willing to implicate Despain in the murder by means of procuring one of Henry's hats from the deceased's lover, Opal, and planting it in Despain's room. In this way, Beaumont extorts the money from Despain after all.

Finally, the novel's ending reveals that the senator himself accidentally killed his son, Taylor Henry, beating him out of rage at his son's having started a fight with Madvig, who supported the senator's election. The senator so valued his office that Madvig's patronage ultimately cost him his son's life. Though Paul Madvig's confession is thrown out as a result of the senator's confession, his friendship with Beaumont is severely compromised.