Electron ionization of rhodanine yields iminothiosulfine ions H-N=CS-S.+,1(.+), which readily communicate with the higher energy cyclic isomer H-N=CS2(.+,) 1a(.+). CBS-QB3 and GAUSSIAN-2 model chemistries predict that one electron reduction reverses the stability order but that the (singlet) neutrals remain connected via a negligible energy barrier. Neutralization-reionization (NR) experiments demonstrate that singlet 1a and its heterocumulene isomer 1b are stable species in the gas-phase. However, the co-generated triplet species readily dissociate into 3S(2)(.+) + HNC. Confirmatory experimental evidence comes from charge reversal (CR) and NR experiments on the cyclic anion H-N=CS2.-, 1a(radical anion-).