  We report the discovery of WASP-8, a transiting planet of 2.25+-0.08 M_Jup on
a strongly inclined eccentric 8.15-day orbit, moving in a retrograde direction
to the rotation of its late-G host star. Evidence is found that the star is in
a multiple stellar system with two other companions. The dynamical complexity
of the system indicates that it may have experienced secular interactions such
as the Kozai mechanism or a formation that differs from the ``classical"
disc-migration theory.
