  The novel PQ mechanism replaces the strong CP problem with some challenges in
a model building. In particular, the challenges arise regarding i) the origin
of an anomalous global symmetry called a PQ symmetry, ii) the scale of the PQ
symmetry breaking, and iii) the quality of the PQ symmetry. In this letter, we
provide a natural and simple UV completed model that addresses these
challenges. Extra quarks and anti-quarks are separated by two branes in the
Randall-Sundrum ${\bf R}^4 \times S^1 / {\bf Z}_2$ spacetime while a hidden
SU($N_H$) gauge field condensates in the bulk. The brane separation is the
origin of the PQ symmetry and its breaking scale is given by the dynamical
scale of the SU($N_H$) gauge interaction. The (generalized) Casimir force of
SU($N_H$) condensation stabilizes the 5th dimension, which guarantees the
quality of the PQ symmetry.
