What is a good book for someone comfortable with maths (but very out of practice) to get up to speed on the topic. Not being scared of not understanding stuff a

What is a good book for someone comfortable with maths (but very out of practice) to get up to speed on the topic. Not being scared of not understanding stuff and needing to learn prerequisites (so doesn’t need to be too easy). Because the wikipedia article isn’t really for learning but it does give a flavour. And it sounds fascinating, sort of like a monte hall problem to me.