Narrow-band emission line images and spectra of the foreground galaxies in the field of TN J0121+1320. Upper left: Narrow-band image of [O II]3726, 3729 at z = 1.4577 integrated from MUSE data cube. We mark the positions of the two [O II] emitters outside the NIRSpec IFU FoV in green and orange, respectively. The blue circle indicates the r = 0.25″ aperture used to extract the foreground galaxy (FG) in the NIRSpec IFU data. It is centered (blue dot) at the spatial position of the emission lines (Sect. 4.1) of FG, as in Fig. 1. The red box shows the FoV of the NIRSpec IFU. Upper right: Narrow-band image of [S III]9533 at z = 1.4577 observed by NIRSpec IFU. The blue dot and circle are the same as in the upper left panel. Middle and lower rows: Spectra extracted at the position of the FG in blue. We also show MUSE spectra of the two [O II] emitters in green and orange, respectively.