... we shall fight on the seas and oceans , we shall fight with in the air , we shall defend our island , whatever the cost may be , we shall fight on the beaches , we shall fight on the landing grounds , we shall fight in the fields and in the streets , we shall fight in the hills ... beaverbrook glanced at the house and saw them to be mesmerised ; ready if called upon , to charge at any enemy , to fly into the jaws of hell , if need be .