Mr. Justice BeaN
delivered the opinion of the court.
It is difficult to understand upon what theory plaintiff can maintain this suit. The right of a court of equity to enjoin an action at law, either by an original suit, or a complaint in the nature of a cross-bill, when the defense is purely of equitable cognizance, or the complainant cannot have full relief at law, is an old and familiar head of equity jurisprudence. The books are full of cases of that kind, but usually the suit is brought by the defendant in the law action, and not by a stranger to the proceedings, unless the cause of suit arises out of some relationship of the plaintiff in such action to the plaintiff in the suit: McCullough v. Abescom Land Improv. Co. (N. J.), 10 Atl. 606; Fisher v. Lord, Fed. Cas. No. 4821; Ferguson v. Fisk, 28 Conn. 501. In this case the plaintiff is not a party to the action sought to be enjoined, and the cause of suit does not grow out of any relationship or dealings between the bank and the plaintiff. It is not apparent, therefore, what right the plaintiff has to interfere in the law action for the purpose of making a defense, either legal or equitable, for Miller. The nature and character of the defense, if any, *365to be made in the law action, is for Miller to determine, and there is no suggestion that he is not capable of doing so. But assuming that a stranger may bring a suit to enjoin the prosecution of an action at law against another for want of a defense thereto, such a suit can only be maintained when the defense at law is inadequate: 16 Am. & Eng. Enc. Law (2 ed.), 365. “Where a court of law can do as full justice to the parties,” says Mr. Pomeroy, “and to the matter in dispute, as can be done in equity, a court of equity will not stay proceedings at law. Equity will not restrain a legal action or judgment where the controversy would be decided by the court of equity upon a ground equally available at law, unless the party invoking the aid of equity can show some special equitable feature or ground of relief; and, in the case assumed, this special feature or ground must necessarily be something connected with the mode of trying and deciding the legal action, and not with the cause of action or the defense themselves”: 4 Pomeroy, Equity (3 ed.), § 1361.
1. Now, under the facts as here claimed by the defendant, Miller’s relationship to it was that of a mere agent or attorney to collect and remit the amount due on the Hel-mick judgment; and while the general rule is that an agent who receives money for his principal is estopped to deny the title, and must return or account for the money to him for whom he received it, this rule does not prevent an agent, when sued by his principal, from showing that he has been divested of the property by a title paramount to that of his principal, or that he has paid over the money or property to one holding such a title: 1 Clark & Skyles, Agency, § 431; Mechem, Agency, § 525; Peck v. Wallace, 19 Ala. 219; Peyser v. Wilcox, 64 How. Prac. 525; Sims v. Brown, 6 Thomp. & C. 5; s. c., affirmed 64 N. Y. 660. The rule in such case is practically the same as that governing the relation of bailor and bailee, and surrendering to a *366paramount title is a good defense: Western Transp. Co. v. Barber, 56 N. Y. 544; Burton v. Wilkinson, 18 Vt. 186 (46 Am. Dec. 145). Miller is therefore not estopped by reason of his relationship to the defendant bank to set up and prove in the action brought by it against him, if he can, that the money in fact belonged to the plaintiff, and that he paid it over on demand prior to t]ie commencement of such action.
2. The point in controversy is whether the money collected by him belonged to the defendant or to the plaintiff. If it was the property of the bank, Miller is liable to it, but if it belonged to the plaintiff, and he paid it over upon demand, such payment will be a complete defense to the law action. These are questions properly triable at law, and according to the procedure applicable thereto. We are of the opinion, therefore, that there is no equity in plaintiff’s proceeding. The decree is reversed, and the complaint dismissed. Reversed.