Arrange fish in a microwave-safe dish, being careful not to crowd the dish.
Combine tomatoes and olives in a small bowl. Pour tomato mixture over fish. Loosely cover dish with plastic wrap if dish does not have a lid. Microwave on high for 2 minutes. If the microwave oven does not have a turntable, then turn the dish 180 degrees and microwave on high for another 3 minutes. Remove from microwave and let stand, covered, for 2 minutes before serving.