Johnny English is an agent with MI-7.
He is one of their best, revered by his colleagues, desired by women everywhere, cool and suave and incredibly collected able to take on any challenge and come out of it with a win no matter what the opposition is. In his dreams, of course, and in the case of the first adventure we 'see' him on, literally that.
In reality, English sits a desk. He puts together intelligence packets real field agents use to prepare for real missions while he stays safe in his chair and can only think about the wondrous things he would do, if only. Luckily for the intelligence communities around the world, those days would never come.
Except they do. And English is finally able to show just how good he really is. Which is not very much, actually. If there were two buttons to push which each did something good, English would find a way to break both, or find a third 'bad' button, or misunderstand the situation and not push anything. But he would goof up with considerable style, looking incredibly dashing in his tuxedo even as things fall down around him, usually through something he did wrong.
English is in his mid 40's when we first encounter him and he will age a few years over the course of his adventures but his ability to mess up and still hide that fact so well will stay as good as ever. And the impossible luck he possesses, not least of all the ability to stay alive, continues. Not to mention that wonderfully insane fact that he can and does get the girl at the end.