Deuterium and proton NMR line shape and T-1 relaxation measurements of solid basketene-d(2) are reported. The compound is polymorphic, exhibiting a low-temperature rigid phase that transforms at 221 K to a plastic phase. Kinetic parameters for the molecular reorientation and self-diffusion in the high-temperature phase are derived, yielding the Arrhenius law parameters A = 4 x 10(13) s(-1), Delta E = (13.8 +/- 0.5) kJ mol(-1) for reorientation and A(d) = 1.2 x 10(13) s(-1), Delta E(d) = (39 +/- 2) kJ mol(-1) for self-diffusion.