Loose Cannons (1990)

Mac, the two-fisted, savvy cop finds that he's being saddled with a new partner, a known burnout, to work with him on a new and difficult case. The new partner is Ellis, an amazing detective, one who puts Sherlock Holmes to shame with his lightning-fast deductions. But he keeps assuming the personalities of entire casts of Television shows. This can be a problem when people begin shooting at them.