More than one expert has observed that musicals with great scores and weak books tend to fail, while those with mediocre scores and solid books have a better chance of succeeding. After all, the first job of every play or film  musical or not  is to tell a good story.
Cell membrane. The cell membrane (also known as the plasma membrane or cytoplasmic membrane) is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells.
Plasma membrane is also a phospholipid bilayer which is essentially a biomembrane that can cover a cell or a cell organelle. For example, lysosome is a cell organelle which contains hydrolytic enzymes and it is bound by a single layer of plasma membrane. While, mitochondria, the powerhouse of the cell is bound by two layers of plasma membrane. Even the nucleus is membrane bound in eukaryotic cells. Hope that helps.