The figure of the thief occupies a surprisingly rich and multivalent position across the depth-psychology corpus. Far from serving merely as a moral category, the thief functions as a symbolic agent whose appearances in dream, alchemical allegory, word-association experiment, and mythological narrative consistently point toward dynamics of concealment, transgression, and psychic appropriation. Jung’s treatment in Mysterium Coniunctionis is the locus classicus: the ‘machinations of the thief’ are declared unavoidable, constituting an integral dimension of the drama of opposites—the shadow that belongs to the light. The thief thus becomes a figure not of simple moral failure but of structural psychological necessity: ‘the thief whom the police do not catch has, nonetheless, robbed himself.’ In Jung’s earlier word-association research, the word ‘thief’ reliably precipitates complex-disturbances, marking it as a carrier of charged unconscious material. Alchemical commentary extends this: the devil as thief ‘pillages the knowledge of God inherent in nature,’ displacing devotion from its proper object. Campbell recovers the figure in hagiographic narrative, where the cry of ‘Thief!’ paradoxically guards spiritual treasure. Zhuangzi’s ironic inversion—the sage as unwitting benefactor of the great thief—introduces a dimension of systemic critique. Together these treatments establish the thief as a liminal figure straddling shadow, complex, and the dynamics of psychic loss and recovery.