What kind of evidence would be needed in order to change any part of cell theory?

In order to change any part of the cell theory, we will have to prove that the cells are not the basic unit of life. We will have to provide evidence that a cell does not distinguish a living thing from a non-living thing. We will either have to prove the spontaneous generation to be true or have to prove that if not cells, then what are the basic units of life. We will also need evidence to prove that a cell does not arise from a pre-existing cell.