Power of property

Sir, i am planning to buy a land. The land was giving a power of property to a lady 30 years back. The kand then sold the land to person 1 then person 1 sold it to person2 and we are planning to buy it from person2. My query is that will there be any legal issues that can be created by the actual owner(who has given power of property to the land) if he comes back. Is it safe to buy such a land? Does the ower has the right to take the land back?