  We show that a natural spinor-helicity formalism that can describe massive
scattering amplitudes exists in $D=6$ dimensions. This is arranged by having
helicity spinors carry an index in the Dirac spinor {\bf 4} of the massive
little group, $SO(5) \sim Sp(4)$. In the high energy limit, two separate kinds
of massless helicity spinors emerge as required for consistency with
arXiv:0902.0981, with indices in the two $SU(2)$'s of the massless little group
$SO(4)$. The tensors of ${\bf 4}$ lead to particles with arbitrary spin, and
using these and demanding consistent factorization, we can fix $3-$ and
$4-$point tree amplitudes of arbitrary masses and spins: we provide examples.
We discuss the high energy limit of scattering amplitudes and the Higgs
mechanism in this language, and make some preliminary observations about
massive BCFW recursion.
