We measure superfast proton diffusion in a proton-exchange membrane (PEM) produced by plasma polymerization. The proton self-diffusion is measured in water-saturated PEMs from the proton autocorrelation function obtained from quasielastic neutron scattering (QENS). 41(3)% of protons in the plasma-produced membrane diffuse at a rate that is an order of magnitude faster than that measured in the commercially available membrane, Nafion, and this is achieved in low hydration conditions. Both molecular dynamic simulations and experimental results are consistent with an assisted superfast diffusion process that may open the way to more powerful fuel cells.