In his remarkably spare drawings from The Underground Sketchbook, Ungerer addresses the sinister realities of the modern world, from meaningless violence to depression. In one untitled drawing, a skeletal figure snaps a picture of an enormous bombing taking place in a distant and empty landscape. In another untitled piece, Ungerer renders a poignant sketch of friendship illustrated by one figure supporting the weight of his friend listlessly seated next to him.
(https://eyeondesign.aiga.org/in-the-wake-of-charlie-hedbo-tomi-ungerer-retrospective-strikes-poignant-note/)