Heading down the rabbit hole…
Qwikiverse maps the references between stories: what Only Murders in the Building nods to, and what nods back. How it works
Wikipedia: Only Murders in the Building
Screenshot of the title card from the first episode of the streaming television series.
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Nothing spotted here yet.
A line quoted, a cameo, a character named after something: if Only Murders in the Building nods to another story, or another story nods to it, spot the first one.