a strong work. according to most histories I have read of the period, attitudes towards the Japanese were not so positive as the protagonist seems to unconsciously express. (we live in more accepting, liberal times). so in that sense, the writer is unconsciously mimicking 1990s British or US feelings rather than the old imperial mindset, but aside from this minor flaw, and the obvious authorial conceit right in the middle of the book, the craftsmanship of this work is a delight. every work has a possible missed opportunity for greatness, and every work has a plausible reworking that would have made it worse, but Orphans clearly minimizes both, resulting in an objectively good work and a subjectively interesting piece.
a craftsman's story at the prime of his powers.
reads to some degree a modern work; according to historical works of the time, the Japanese and British communities did not mix so much. the work isn't totally unbelievable (aside from unreliable narrator/ deliberate time jump effect), it's just that it's modern UK sensibilities transposed on 1920s Shanghai.
aside from this concern, narratologically / novelistically speaking this is a premier work. it's evocative, well-written, action-/plot-/character-balanced and tight.