小说描绘了一八七零年普法战争期间，有一辆法国马车在离开敌占区时，被一名普鲁士军官扣留。军官一定要车上的一个绰号叫羊脂球的妓女陪他过夜，否则马车就不能通过。羊脂球出于爱国心断然拒绝，可是和她同车的有身份的乘客为了各自私利，逼她为了大家而牺牲自己，羊脂球出于无奈而作了让步。可当第二天早上马车出发时，那些昨天还苦苦哀求的乘客们却突然换了一副嘴脸,个个疏远她，不屑在与她讲话。（The novel depicts a French horse cart captured by a Prussia officer when it tried to leave the occupied area in the Prussia-France War in 1870. The officer insisted that the prostitute called Ball of Fat in the cart to sleep with him, otherwise the cart would not pass. The Ball of Fat refused the request out of patriotism. However, the upper-class passengers in the cart forced her to make sacrifice for their own sake. The Ball of Fat had to agree. However, on the next day when the cart started, the passengers gave cold face to her and forgot that they were begging her on the previous day. ）