There are 101 idioms with cartoons, followed by a dialogue or a description. At the back are translations of the dialogues and a list of the idioms in alphabetical order and by key images. So, if you know you want to something to do with 'dogs' for example, you can look up dog and find the idioms associated with that image.
I can't recommend this highly enough. It helps you practise your French without even realising that's what you are doing. I'm intending to order the proverbs as well! it is a real bargain. It was worth that just for the laughter it brought.