I've heard the phrase so many times, but only now am wondering where it comes from.
I know it is used to mean that someone has been tricked, or has in some way fallen for a trap.
e.g.
Bob: So I ended up buying the volcano insurance from the salesman in the end.
Geoff: Wow! He stitched you up like a kipper.
But what on earth have "kippers" got to do with anything?
Best Answer
I think it's a mixture of similes. He may have stitched you up, or he may equally have done you. In the latter case, he may have done you brown (like a piece of meat is well done) or done you like a kipper (even more so, since kippers are done, or smoked, for many hours). Combining the two is a jocular turn of phrase (like without a paddle to stand on) that is easily picked up by people looking for a strong or picturesque phrase without worrying much about its origins.
Edit: I notice (e.g. here) that done up like a kipper is also widely used. The problem with criminal argot of this era is "Minder", and the Godfather Effect; it is probably impossible now to disentangle which phrases were in use in the 70s/80s and picked up by the scriptwriters, and which were invented for effect by the scriptwriters, and picked up by the wide boys of South London or Essex.