  A solvable current-current deformation of the worldsheet theory of strings on
$AdS_3$ has been recently conjectured to be dual to an irrelevant deformation
of the spacetime orbifold CFT, commonly referred to as single-trace $T\bar{T}$.
These deformations give rise to a family of bulk geometries which realize a
non-trivial flow towards the UV. For a particular sign of this deformation, the
corresponding three-dimensional geometry approaches $AdS_3$ in the interior,
but has a curvature singularity at finite radius, beyond which there are closed
timelike curves. It has been suggested that this singularity is due to the
presence of "negative branes," which are exotic objects that generically change
the metric signature. We propose an alternative UV-completion for these
geometries by cutting and gluing to a regular background which approaches a
linear dilaton vacuum in the UV. In the S-dual picture, a singularity
resolution mechanism known as the enhan\c{c}on induces this transition by the
formation of a shell of $D5$-branes at a fixed radial position near the
singularity. The solutions involving negative branes gain a new interpretation
in this context.
