  47 Tuc was the first globular cluster observed to be $\gamma$-ray bright,
with the $\gamma$-rays being attributed to a population of unresolved
millisecond pulsars (MSPs). Recent kinematic data, combined with detailed
simulations, appears to be consistent with the presence of an intermediate mass
black hole (IMBH) at the centre of 47 Tuc. Building upon this, we analyse 9
years of \textit{Fermi}-LAT observations to study the spectral properties of 47
Tuc with unprecedented accuracy and sensitivity. This 9-year $\gamma$-ray
spectrum shows that 47 Tuc's $\gamma$-ray flux cannot be explained by MSPs
alone, due to a systematic discrepancy between the predicted and observed flux.
Rather, we find a significant preference (TS $=40$) for describing 47 Tuc's
spectrum with a two source population model, consisting of an ensemble of MSPs
and annihilating dark matter (DM) with an enhanced density around the IMBH,
when compared to an MSP-only explanation. The best-fit DM mass of 34 GeV is
essentially the same as the best-fit DM explanation for the Galactic centre
"excess" when assuming DM annihilation into $b\bar{b}$ quarks. Our work
constitutes the first possible evidence of dark matter within a globular
cluster.
