I understand the problems of ecranisation rights, that it may be already sold or they won't give it to you. But there is a wonderful thing called retelling. If I understand correctly there are no copyright limits, you can take well known plot and move its characters +
and on the other side there will be curiosity about new interpretation of the known plot, almost like ecranisation of book/novel. And if the company has screenwriters that work with ready scripts, they may be able to make it,
in the other world, recreating it again and in new way. On one hand creators get enough freedom to shape the plot and characters. On the other hand a ready story doesn't allow plot to collapse and holds it together. For the viewers this looks fresh along with the original plot,