The hydrolysis of isatin aldazine4a–dafforded the unexpected 3,3′-(hydrazine-1,2-diylidene)bis(indolin-2-one) (5) and 1,2-di(arylidene)hydrazines6a–dthrough dual hydrolysis of4a–d. A mechanism to explain the formation of5and6a–dwas proposed. In addition, the hydrazinolysis of4a–dyielded 3-hydrazonoindolin-2-one (2) and 1,2-di(arylidene)hydrazines6a–dinstead of hydrazones17a–d, while hydrazinolysis of isatin ketazine5gave the expected 3-hydrazonoindolin-2-one (2). These results indicated the ability of the title compounds for unusual hydrolysis and hydrazinolysis reactions.