1. The first and second exceptions may be disposed of together. The notes given by the plaintiff to the defendants upon the adjustment of the accounts between them in May, 1886, were secured by pledge of the money which the plaintiff sought to recover in this action, and were admissible in evidence for the defence, upon the issue whether, if they took that money, they were entitled to retain it as collateral security for the notes. The record of the former suit, in which the notes had been pleaded in set-off against the plaintiff, showed that the suit was still pending; as it had not gone to judgment, the *213notes were not extinguished, and the record offered by the plaintiff was immaterial, and was rightly excluded. Until the notes were extinguished, the right to retain the collateral pledged as security for their payment remained in the defendants.
2. The next class of exceptions is to the admission of evidence that during the period covered by the transactions upon which the plaintiff’s suit is founded, he committed other frauds upon the defendants in other transactions in which they lent him money. This evidence was introduced in support of the defendants’ contentions that they took no money from the safety vaults, and that they found in the vaults nothing but worthless bundles secretly substituted by the plaintiff for the money which he had himself fraudulently removed.
Acts which are part of one general scheme or plan of fraud, designed and put in execution by the same person, are admissible to prove that an act which has been done by some one was in fact done by the person who designed and pursued the plan, if the act in question is a necessary part of the plan. Commonwealth v. Robinson, 146 Mass. 571, 577. See also Wiggin v. Day, 9 Gray, 97 ; Lynde v. McGregor, 13 Allen, 172; Jordan v. Osgood, 109 Mass. 457; Haskins v. Warren, 115 Mass. 514; Horton v. Weiner, 124 Mass. 92; Commonwealth v. White, 145 Mass. 392. And the plan itself, and the acts done in pursuance of it, may all be proved by circumstantial evidence. Commonwealth v. Robinson, ubi supra. The transactions shown in the evidence in the present case were very strange and peculiar. One reasonable explanation of them is that they disclose a plan by which the plaintiff designed to cheat the defendants, after first obtaining their confidence, by showing them that he had money in large amounts, by intrusting his money to their keeping, borrowing from them upon their belief that they had it in their keeping, and, when his borrowing had reached a sufficient extent, by secretly removing his money from their possession by sleight of hand, and substituting in its stead something of no value. All the transactions put in evidence were between the same parties, during the same period of time, and were of the general character of confidence games, carried through by deception and jugglery. They may well have been parts of a single plan, the chief end of which was the abstraction by the *214plaintiff of the money from the safety boxes; and if so, any acts done by him in pursuance of that plan were competent to show that it was he who did the act which was its necessary culmination if successfully carried through.
3. The remaining exception is to the exclusion of evidence that the plaintiff had been acquitted in a criminal prosecution for one of the frauds, evidence of which was admitted against him. But that acquittal was res inter alios, like the withdrawal of suits by other parties in Haskins v. Warren, 115 Mass. 514, 538. Because the defendants were strangers to the judgment offered, it could not affect them. Commonwealth v. Waters, 11 Gray, 81. Cluff v. Mutual Benefit Ins. Co. 99 Mass. 317, 325. Parker v. Kenyon, 112 Mass. 264. Exceptions overruled.