My vote goes to “Hide-and-Seek” by Pavel Tchelitchew.

From afar, this painting simply appears as a central child climbing a tree, one imbued with vibrant reds and greens.

However, upon closer inspection, there are actually screaming babies and children being set to flames on the outsides of the tree, and a terrorizing mix of fingers and bones are overlaid throughout the image. The entire image is frighteningly raw, with human body parts seemingly in every junction.

This entire painting is an example of “simultaneous images,” a technique where multiple subjects are depicted over each other in an ambiguous fashion.

Tchelitchew painted Hide-and-Seek in 1942, at the height of World War 2. In many ways, it perfectly fit the time, illustrating the themes of agitation and human destruction that pervaded societal consciousness.

His work fits into a more general early-20th century mood, aptly called the “Age of Anxiety.” Between two world wars, a crippling depression, the rise of totalitarian governments, and seemingly endless moral decadence, Hide-And-Seek fits right in with other disturbing pieces of art from these decades, some of which are shown below.

Guernica, one of Picasso’s most famous works. He painted this in response to the Nazi bombing of a civilian town during the Spanish Civil War, illustrating a mess of fire, bodies, and destructive elements.

The Laugh, a painting by Umberto Boccioni whose overlaid images of wine, flashing lights, and general excess matched the idea of moral decadence and worldly corruption.

While Hide-and-Seek’s raw imagery still takes my spot for the most disturbing piece of art, these other works closely follow. Each painting is just one of many penetrating, unsettling works from the early 1900s.