  The CKM angle $\gamma$ is determined from $C\!P$-violating observables
measured in ${B^\pm \to D[ K^\mp \pi^\pm\pi^\pm\pi^\mp] h^\pm}$, $(h = K,\pi)$
decays, where the measurements are performed in bins of the decay phase-space
of the $D$ meson. Using proton-proton collision data collected by the LHCb
experiment at centre-of-mass energies of $7, 8$ and $13\,\text{TeV}$,
corresponding to a total integrated luminosity of $9\,\text{fb}^{-1}$, $\gamma$
is determined to be \begin{equation*} \gamma = \left( 54.8 \: ^{+\:6.0
}_{-\:5.8} \: ^{+\:0.6}_{-\:0.6} \: ^{+\:6.7}_{-\:4.3} \right)^\circ,
\end{equation*} where the first uncertainty is statistical, the second
systematic and the third from the external inputs on the coherence factors and
strong phases of the $D$-meson decays.
