What’s a good standalone and or COMPLETED series that left readers wanting more?

I’m looking for a two - fold. I’m in search of a standalone book that just was like “whoa- that was supremely fantastic” and or a COMPLETED series worth getting into. I’m so tired of getting into a book series only to learn there are 3 more books to be released and waiting 2-3 years for the next installment or in a few cases the next installment NEVER being released. Suggestions?