Ground-based 140″ × 140″ DES g, r, y + z image of the galaxy cluster WHJ0400-27, with coordinates centred on the BCG (z_cl, spec = 0.626, (RA, Dec)_J2000 = (60.04888, −27.11959) deg). The cyan and red circles indicate the QSO pair (z_spec = 1.345). The candidates for the third QSO image, with colours consistent with those of the QSOs, are enclosed by magenta squares (ID1-4-5-6). The dotted green rectangle represents the approximate region where the lens model predicts the position of the third image. Photometric cluster members are marked with orange circles. The dashed white line is the critical line predicted by the best-fit lens model at the QSO redshift.