George Tooker painting of American Immigration Control with people queuing up to visit or move to America.
Subway Rather melancholic painting by George Tooker with the banisters and turn styles creating barriers
George Tooker Self Portrait with the hand obscuring the face or creating a barrier

George Tooker double portrait - door creates a barrier between the two figures and different moods.
George Tooker - slightly scarier image - is that a second figure or somekind of twisted reflectionhttp://www.tendreams.org/tooker.htm good webpage with good images that you can grab using print screen