It's not based on a true story. The plot and characters of Mr Inbetween are the result of the writer's imagination and creative process. Although it might draw inspiration from real-life situations to some extent, it's not a direct account of actual events.
One key element is the realistic portrayal of the criminal world. Since it's based on a true story, it likely shows the gritty details, power dynamics, and the unwritten rules that exist in that world.
I'm not sure specifically as there could be many stories with this name. It might be about the days in between significant events, like the days in between holidays or important life moments.
"Missing Xiao Shan" was not a literary work of his, but one of his novels. It was published in 1939. The author of the novel was famous in modern China.
Ba Jin's Missing Mr. Lu Xun was selected from his novel collection Missing Mr. Lu Xun. This collection of novels included Ba Jin's works and thoughts about Lu Xun, reflecting his reverence and nostalgia for Lu Xun.