  We give a systematic analysis of forward scattering in 3$+$1-dimensional
quantum gravity, at center of mass energies comparable or larger than the
Planck energy. We show that quantum gravitational effects in this kinematical
regime are described by means of a topological field theory. We find that the
scattering amplitudes display a universal behaviour very similar to two
dimensional string amplitudes, thereby recovering results obtained previously
by 't Hooft. Finally, we discuss the two-particle process in some detail.
