Say you're making a fish-out-of-water action comedy about a lawman from the streets paired improbably with a mild-mannered dental-supply salesman. What's your first move? Cast Eugene Levy, says Levy: ''If the playground for this is the back alleys and the streets of the inner city, then just kind of...put me in it. You don't have to do too much.'' And there you have The Man, where Levy is haplessly matched with a hard-boiled FBI agent (Samuel L. Jackson) in a case of mistaken identity. But don't write this off as a high-concept buddy pic just yet. ''What I held up was Midnight Run, which is a favorite of mine and Sam's,'' says Levy. So why not get Midnight director Martin Brest? ''He was a name that came up early on. But I think he came with a price tag.'' Too bad. Did anyone run a price check on Charles Grodin?