Read my first Agatha Christie this week. What next?

I had never read a ‘whodunnit’ style mystery before, decided to read ‘And then there were none’ the other night as a bit of a palette cleanser, and I thoroughly enjoyed it.

So I have two questions. Can somebody recommend me the 2 or 3 best of Agatha Christie’s novels so I could give them a go too?

Second recommendation would be for any truly great books in this same kind of ‘whodunnit’ genre by different authors?

Thank you guys. I go through anywhere from 1-4 books a week, so I’ll gladly take all the recommendations on board!