Catherine Lim authored a collection of stories called Or Else, The Lightning God and Other Stories of which Or Else The Lightning God is the last in the collection. This collection follows on from her earlier work, Little Ironies and continues the themes of selfishness, ignorance, pretentiousness and certainly misunderstanding. Lim uses every day situations to highlight the hidden difficulties in all social situations and the consequences when they are eventually exposed. She focuses on women and challenges their "place" in society.
Loyalty and family obligation is the main theme of Or Else, the Lightning God as the traditional clashes with the modern. Two women with totally different perceptions of their roles and status within the family challenge the concept of the younger generation respecting its elders without the older generation showing respect for the youth. "The young must respect the old Margaret, or they will be punished." In order to work, both generations need to have a mutual respect for each other.
The conflicting personalities result in the younger woman evicting the older woman from her home after she overhears her complaining about being mistreated by her daughter-in-law. The bitter and uneducated mother-in-law will invoke the "lightning god" to strike down her modern, career-oriented daughter-in-law as she has committed the most heinous crime by, in her subjective opinion, showing no respect for the elderly.