  The Triple Deck model is a classical high order boundary layer model that has
been proposed to describe flow regimes where the Prandtl theory is expected to
fail. At first sight the model appears to lose two derivatives through the
pressure-displacement relation which links pressure to the tangential slip. In
order to overcome this, we split the Triple Deck system into two coupled
equations: a Prandtl type system on $\mathbb{H}$ and a Benjamin-Ono type
equation on $\mathbb{R}$. This splitting enables us to extract a crucial
leading order cancellation at the top of the lower deck. We develop a
functional framework to subsequently extend this cancellation into the interior
of the lower deck, which enables us to prove the local well-posedness of the
model in tangentially real analytic spaces.
