Most of Zweig's stories deal with obsession, and are told by a secondary narrator, that is one relating the tale to the primary narrator, assumed to be the author. This story, one of his finest novellas, is about two forms of obsession, one by a young man who is a compulsive gambler, and one by a middle-aged widow who becomes briefly infatuated with him.
Told with Zweig's usual attention to emotional nuance, it's a study in gambling mania to put alongside Dostoevsky, and includes some outstanding passages, including about 4 pages on the observation of hands to derive character. The precision of his writing is always a delight, but in this story it combines with the description of a brief but destructive passion. There's a contrast between the clarity of the prose and the turmoil of the scenes described, explained by the tale being a confession by an intelligent woman 25 years after the event of an exceptional passion.
Many of Zweig's stories are structured in this way, desperate confessions of past indiscretions by people wanting to unburden themselves to the unnamed narrator, presumed to be Zweig. While this is a simple narrative device, and not very convincing, it lends Zweig himself a personality of someone to be confided in, which adds some credibility to his narrator characters.
This is definitely one of Zweig's best stories, tightly conceived and told, and entirely convincing.