Picture this: Olga's life so far has sucked. She's gone from being a beautiful rich girl in a loving home, to an orphan who can't even afford to buy a pair of stockings. She thinks she'll never see her home again. But then, out of nowhere, who arrives to save the day? No, not Superman. Vera.
A deus ex machina is when something or someone suddenly arrives to solve an unsolvable problem. Olga's unsolvable problem? She's poor and needs to find a husband to support her, but she's too run down for a rich man to take interest in her. But then Vera, whom we've never met before, literally runs into Olga: "One day, almost knocking her off her feet, her one-time friend Vera rushed like a whirlwind out of a telephone booth, in a hurry as always, loaded with parcels, with a shaggy-eyed terrier whose leash immediately became wound twice around her skirt" (12). Immediately we know who she is. She's a rich busybody, who is probably very chipper and annoying but is also probably the answer to Olga's prayers.
We get a single line describing Vera's personality: "Vera adored arranging things, be it a party with punch, a visa, or a wedding. Now she avidly took up arranging Olga's fate" (13). Jackpot. Olga's dreams are within reach. Vera's going to set her up on a date, get her a rich husband, and it's going to be a happy ending. Perfect.
Almost. Vera does set Olga up on a date. She does get her a rich husband. But there is no happy ending, because Olga dies in childbirth. Vera's a pretty sucky deus ex machina, then, isn't she? In the same way that Nabokov plays with our expectations of Olga, he deliberately misleads us with Vera. Didn't you feel crushed after you thought there was a happy ending, but it turned out to be another death? We wouldn't be surprised if that's how the Russian émigrés felt about their homeland. They had hoped that everything would turn out right, but it never did.
While Vera is off living her perfect life, in her perfect house, with her rich husband, Olga is dead. Isn't that something? If you want to read a little more about how much that sucks, head over to the Character Roles: Foils section.