Reformation is almost always asserted as a preliminary to some other remedy which is to be pursued. This equitable remedy is available when a written contract or conveyance fails to express the agreement of the parties, due to the fraud or misrepresentation of one party and the mistake of the other. Restatement of Contracts § 491 (1932). In such a situation, rescission is an alternative to the innocent party. Restatement of Contracts § 491, Comment (a) (1932). Reformation is also available in the case of mutual mistake. Restatement of Contracts § 504, Comment (a) (1932).