We report that coupling of molecular biaxiality and chirality is effective for blue phase stabilization. We show a U-shaped binaphthyl derivative with a cubic blue phase and some T-shaped compounds with an amorphous blue phase III (BPIII). We designed a ternary system consisting of a conventional nematic mixture, a T-shaped BPIII stabilizer, and a chiral dopant. BPIII of the system exhibited high transmittance, submillisecond response, and hysteresis-free switching at room temperature. Amorphous BPIII, with a level of symmetry equal to that of an isotropic liquid, is thought to have a superior potential for use in next-generation displays.