We construct hairy rotating black hole solutions in three dimensional
Einstein gravity coupled to a complex scalar field. When we turn on a real and
uniform source on the dual CFT, the black hole is stationary with two Killing
vectors and we show that there is no inner horizon for the black hole and the
system evolves smoothly into a Kasner universe. When we turn on a complex and
periodic driving source on the dual CFT with a phase velocity equal to the
angular velocity of the black hole, we have a time-dependent black hole with
only one Killing vector. We show that inside the black hole, after a rapid
collapse of the Einstein-Rosen bridge, oscillations of the scalar field follow.
Then the system evolves into the Kasner epoch with possible Kasner inversion,
which occurs in most of the parameter regimes. In both cases, one of the metric
fields obeys a simple relation between its value at the horizon and in the
Kasner epoch.Comment: 35 pages, 14 figure