Here is a really great atomic age original half-sheet movie poster for the obscure cautionary Curt Siodmak sci-fi thriller The Magnetic Monster (1953), featuring an expanding radiomagnetic isotope being transported to be extinguished before it throws the earth off its axis. The pseudoscience is convincingly presented and the notion of a “monster” isotope growing out of control has a sort of universal fear factor.
Super sci-fi poster features effective “electron orbit” focal point with inset drawings of various sorts of panic seen in slightly less epic fashion in the film itself.