The story opens with Francis Macomber, Margot Macomber, and Robert Wilson all having a gimlet with lunch. Gloom is in the air but everyone is "pretending that nothing had happened" (1.1). A crowd of natives has just carried Francis Macomber triumphantly into camp. Macomber, a good-looking athletic type, has just blown it on a lion hunting adventure and now everyone knows he's a coward. Macomber's wife can't contain her resentment and humiliation about her husband's breakdown on the hunt. This is not a proud moment for the Macombers.
Meanwhile, Francis Macomber cannot stop worrying about his failure. What will other people think? Wilson, a hardscrabble English hunting guide, tries to console him, but Macomber continues to harp on his spinelessness, to the point where he's getting on Wilson's nerves (and ours). Macomber decides he wants to hunt buffalo to try to make up for his screw-up. Wilson can't get over how cruel Margot Macomber is, but then again he thinks that all American women are cruel, and hey, maybe Macomber deserves it. In any case, Margot is awfully good-looking.
We flash back to the night before. Macomber is in his tent, wide-awake. A lion has been roaring all night, which is frankly terrifying. How will he face that beast tomorrow? He wakes up and can't hide his fear, but they all head off for the hunt anyway.
The hunt is a total and complete disaster. Macomber's hands are shaking, and though he hits the lion with a bullet, he doesn't want to go in and finish the job, so Wilson does it for him. Macomber's wife is humiliated that her husband couldn't finish off the lion, so she kisses Wilson on the mouth. Way to add insult to injury.
We find out that Margot and Francis are a well-to-do American couple. The safari was but one of the many adventures Macomber has enjoyed, as a wealthy and athletic man. They're the perfect pair: she's beautiful, and he's rich. Macomber isn't fazed by his wife's disgust, having experienced it before. Though she harps at him, he's not worried – he's too rich for her to leave him.
The next day, Macomber wants to give it another go, this time hunting buffalo. The hunt goes differently this time, with Macomber getting in a good shot. He is stoked. As they're about to celebrate a victory, Wilson and Macomber discover that the buffalo isn't actually dead, so they have to bushwhack their way after the animal. When they find the buffalo, it charges at Macomber, who starts to fire, but his aim is off. Wilson fires too. Finally, Macomber gets the buffalo, but just at that moment, Margot takes a shot from the car that hits Macomber in the skull and kills him. Wilson tells her that there will be an investigation and makes it clear that he thinks she killed Macomber on purpose. Now there's an ending.