Short film ideas with no people?

How big is the extent of Law of Rights to protect people's original ideas in film business?

• Is this the case we can say that breaks the Law: the Western atmosphere "The Magnificent Seven" had well-knownly derived from a Japanese film "Seven Samurais"? If yes, What had the maker of "The Magnificent Seven" to do with the maker of "Seven Samurais"? Pay sum of money to have permission to use the right? If no, is it enough to say in "The Magnificent Seven" before screening like this: Based on "Seven Samurais," or something else? Curious very much, please enlighten me. Thank you.

• Answer:

  i wonder this myself because there are alot of tales that have to be remade to appeal to american audiences.......there's an anime i have to make a film out of.......