Physicists no longer say that the invisibility cloak of Harry Potter, the vanishing car of James Bond or the Invisible Man are an impossibility. It may be possible to make things invisible by putting a thin layer of a specially patterned material in the way. Appropriately made, these materials with repeated three dimensional structures less than the wavelength of the radiation used will break the traditional laws of optics and magnetics because they employ quantum effects. For example, if you look at a beam of light shone towards you through a sheet of glass, it has bent to the right as shown below in blue. These materials obeying the conventional laws of optics are called Right Hand Materials RHM. With the new stuff shown below in green, light, or other electromagnetic radiation, would bend to the left. With an appropriate construction, it would not get through at all.
The new structured materials are called Left Hand Metamaterials LHM, first proposed by Russian physicist Victor Veselago in 1968.