There’s a moment deep into the knives-out rhetorical melee of David Mamet’s Glengarry Glen Ross where a soulless real estate salesman shows a flash of tenderness. Washed-up veteran Shelly Levene (Bob Odenkirk) has just closed a massive sale—“eight units eighty-two grand”—and can’t believe he’s still got it: “I did it. Like in the old days, Ricky. Like I was taught,” he gushes to his protégé Richard Roma (Kieran Culkin). Roma, struck by a bit of sentimentality toward his mentor, responds, “Like you taught me.” Aww. But catch Levene and Roma and their colleagues, each one nastier than the next, at any other moment, and they’re more likely to be ripping each other’s throats out in search of the next actionable customer lead.

For a story to hold our attention, we need to care, even just a little bit, about the characters—to...