Zoom image of the jet base in AIA 171 Å. The FOV for this figure is presented as the blue square in Fig. 1d. The null-point-like structure at the jet base is indicated with a white arrow (panel a). The jet is initiated under the arcade (green arrow) following a small filament eruption (red arrow). This small filament pushes the arcade towards the null-point-like structure, which leads to the jet flowing towards the filament (white arrow in panel b–d) in the southwest. This flow is bidirectional, as we observe the second branch, which flows toward the north, is indicated with cyan arrows in panels c-d. The null-point-type structure collapses into the breakout current sheet (BCS) The latter is marked using yellow arrows in panels b–d; see also the animation online).