In a bowl, mix the flour, salt and pepper. Lighty coat the fish fillets with the flour mixture.
Heat the olive oil in a large frypan over medium-high heat, and cook the fish fillets 3 minutes on each side, until golden brown. Reduce heat to medium-low and brush fillets with oyster sauce. Cover frypan and continue cooking 5 minutes, or until fish is easily flaked with a fork.