  We study the interior dynamics of a top-down holographic superconductor from
M-theory. The condense of the charged scalar hair necessarily removes the inner
Cauchy horizon and the spacetime ends at a spacelike singularity. Although
there is a smooth superconducting phase transition at the critical temperature,
the onset of superconductivity is accompanied by intricate interior dynamics,
including the collapse of the Einstein-Rosen bridge, the Josephson oscillations
of the condensate, and the final Kasner singularity. We obtain analytically the
transformation rule for the alternation of different Kasner epochs. Thanks to
the nonlinear couplings of the top-down theory, there is generically a
never-ending chaotic alternation of Kasner epochs towards the singularity. We
compute the holographic complexity using both the complexity-action and the
complexity-volume dualities. In contrast to the latter, the complexity growth
rate from the complexity-action duality has a discontinuity at the critical
temperature, characterizing the sudden change of the internal structure before
and after the superconducting phase transition.
