To this day, it's hard to find any illustrator that hasn't been influenced by Searle's extra-ordinary work. This book is full of these characters (120 drawings in all!), each one so unique and real - you can't help thinking that you've met people like them or seen some in a movie. His deceptively loose and simple line is so descriptive of the character's appearance and soul yet distorting and exaggerating their shape for comical effect.
There's a very good review of this book to be found on Matt Jones' Ronald Searle tribute blog http://ronaldsearle.blogspot.co.uk/2006/07/molesworth.html together with many more illustrations.