  We show that compatibility of supersymmetry with exact semi-classics demands
that in calculating multi-instanton amplitudes, the "separation" quasi-zeromode
must be complexified and the integration cycles must be found by using complex
gradient flow (or Picard-Lefschetz equations.) As a non-trivial application, we
study $\mathcal N=2$ extended supersymmetric quantum mechanics. Even though in
this case supersymmetry is unbroken, the instanton-anti-instanton amplitude
(naively calculated) seems to contribute to the ground state energy. We show,
however, that the instanton-anti-instanton event consists of two parts: a
fermion-correlated and a scalar-correlated event. Although both of these
contributions are naively of the same sign and the latter is superficially
higher order in the perturbative coupling, we show that the two contributions
exactly cancel when they are evaluated on Lefschetz thimbles due to their
relative Hidden Topological Angles (HTAs). This gives strong evidence that the
semi-classical expansion using Lefschetz thimbles is not only a meaningful
prescription for higher order semi-classics, but a necessary one. This
deduction seems to be universal and applicable to both supersymmetric and
non-supersymmetric theories. In conclusion we speculate that similar
conspiracies are responsible for the non-formation of certain molecular
contributions in theories where instantons have more than two fermionic
zeromodes and do not contribute to the superpotential.
