  The formation of black holes or naked singularities is studied in a model in
which a homogeneous time-dependent scalar field with an exponential potential
couples to four dimensional gravity with negative cosmological constant. An
analytic solution is derived and its consequences are discussed. The model
depends only on one free parameter, which determines the equation of state and
decides the fate of the spacetime. Without fine tuning the value of this
parameter the collapse ends in a generic formation of a black hole or a naked
singularity. The latter case violates the cosmic censorship conjecture.
