One scene from The Ordeal, a section of the classic First Doctor story The Daleks, made me chuckle quite a bit due to the old visual effects and general atmosphere. First, after dropping a TARDIS key into a wall panel, the First Doctor told Susan "the power's running away!", in much the same way a parent would say something to their child that's not entirely true, but is ultimately harmless (which makes some level of sense considering she's his granddaughter, but it's still amusing).