This paper gives a brief description of how Maxwell's equations are expressed in the language of differential forms and use this to provide an elegant demonstration of how the method of images (well known in electrostatics) also works for electrodynamics in the presence of an infinite plane conducting boundary. The paper should be accessible to an advanced undergraduate or a graduate student whose background includes a development of electromagnetism including the differential form of Maxwell's equations and preferably including a relativistic approach; special relativity from the point of view of Minkowski space (and not merely a derivation of the Lorenz transformations); and an introduction to the use of differential forms, most easily met in a course on general relativity.