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eroock
Since: Sep, 2012

Alice and Bob are the main characters of "A & B" series of detective novels and have their crazy, high-stake adventures. The autor writes a short story about Jim, a regular guy, who gets an adventure on his own. Half-way through, it is revealed to be a spin-off of the "A & B" series, and Alice and Bob show for a cameo to sort the resulting mess and help out Jim, then leave. What for Jim so far was an extreme, life-shattering and changing experience, from Alice and Bob perspective (and the standard fare of their own series) is just a minor altercation, something they would be dealing as a menial PI job between their typical adventures.
Effectively: the spin-off story is about the kind of mundane case the characters just mention in passing when dealing about their detective work, but from perspective of the main character of said story, this is the case of a century.