Most people when they think of a hook in a story think of the Hollywood, high-concept version, something like:
Martha Harry was the best spy in the business, but what no one knew, not even her bosses at the CIA, was that Martha was a vampire.
Which is fine if you’re writing a high-concept story of that kind, but hooking the reader at the start of a story is more to do with phrasing and learning how to pose a question without a question mark.
Martha Harry, or ‘Buckets’ as she was known to anyone who had been at school with her, lived in a two bedroom apartment in Manhattan.
There is now a question that will appear in the mind of anyone who reads that opening: why was she called 'Buckets'? It doesn't need to be a question that the whole book is about answering, it just keeps the reader on the other end of the line, an especially useful technique at the start of a book.
If I were to rephrase it as: