  The construction of field theories with space-time symmetries, including
tensorial charges (i.e. of M-theory type), initiated in hep-th/9907011, is
extended to include interaction. For SO(2,2) gravity in a tensorial space-time,
with space-time symmetry consisting of Lorentz generators and "translations",
represented by second-rank antisymmetric tensor, the cubic interaction terms
are constructed by requirement of maintaining the gauge invariance property of
theory. This interaction is essentially unique.
