The English artist Damien Hirst first used formaldehyde in 1991, when he placed a 14-foot tiger shark in a tank filled with the noxious compound and called it The Physical Impossibility of Death in the Mind of Someone Living. Returning to the eerie technique time and time again, Hirst has preserved a number of other species—sheep, doves, even a zebra—sometimes bisecting the creatures, sometimes removing their internal organs, sometimes adding objects that symbolize another time, say, a chainmail glove! Visceral, spiritual, and, in the case of his “unicorn” (made in 2008 and titled The Dream) mythological, these are wordless essays on mortality and imagination. At Gagosian, in the first exhibition dedicated to this vein of Hirst’s practice, 20 formaldehyde works will be on view. The most recent was completed last year, in 2021. —Elena Clavarino