The Gate concerns a middle-aged married couple, Oyone and Sosuke, who married for love in their student days. The couple first suffered exclusion from society due to their ill-advised marriage; as the novel opens, they languish in ennui because they no longer feel passion for one another. However, Oyone's ill health and a visit from Sosuke's younger brother provoke a marital crisis which becomes the central diegesis.
Thematically and by the author's own reckoning, The Gate is the third in a trilogy of novels begun by Sanshiro (1908) and (1909). All three novels deal with the themes of self-knowledge and responsibility - on the one hand, accountability to society, and on the other, responsibility to one's own emotions. However, the three novels do not share characters.