A model-dependent amplitude analysis of the decay B 0 → D(K S 0 π + π −)K ∗ 0 is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb−1, recorded at $$ \sqrt{s}=7 $$ and 8 TeV by the LHCb experiment. The CP violation observables x ± and y ±, sensitive to the CKM angle γ, are measured to be $$ \begin{array}{l}{x}_{-}=-0.15\pm 0.14\pm 0.03\pm 0.01,\hfill \\ {}{y}_{-}=0.25\pm 0.15\pm 0.06\pm 0.01,\hfill \\ {}{x}_{+}=0.05\pm 0.24\pm 0.04\pm 0.01,\hfill \\ {}{y}_{+}=-{0.65}_{-0.23}^{+0.24}\pm 0.08\pm 0.01,\hfill \end{array} $$ where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the D → K S 0 π + π − amplitude model. These are the most precise measurements of these observables. They correspond to γ = (80 − 22 + 21 )° and $$ {r}_{B^0}=0.39\pm 0.13 $$ , where $$ {r}_{B^0} $$ is the magnitude of the ratio of the suppressed and favoured B 0 → DK + π − decay amplitudes, in a Kπ mass region of ±50 MeV around the K *(892)0 mass and for an absolute value of the cosine of the K *0 decay angle larger than 0.4.