This happened to a former employer back in 2008. They sold us on their A-team and we got the guys they hid in the backroom closet. We cancelled the contract after their second code dump. They threatened to sue and my former CEO openly challenged them to. In the end they backed off.
Unfortunately this happens in all sorts of consultancies and agency work. The partner makes the sale and (hopefully) at least reasonably supervises the associates or others doing most of the actual work.
