  This paper presents a measurement of $ZZ$ production with the ATLAS detector
at the Large Hadron Collider. The measurement is carried out in the final state
with two charged leptons and two neutrinos, using data collected during 2015
and 2016 in $pp$ collisions at $\sqrt{s} = 13$ TeV, corresponding to an
integrated luminosity of 36.1 fb$^{-1}$. The integrated cross-sections in the
total and fiducial phase spaces are measured with an uncertainty of 7% and
compared with Standard Model predictions, and differential measurements in the
fiducial phase space are reported. No significant deviations from the Standard
Model predictions are observed, and stringent constraints are placed on
anomalous couplings corresponding to neutral triple gauge-boson interactions.
