  We present an observational study of the plasma dynamics at the base of a
solar coronal jet, using high resolution extreme ultraviolet imaging data taken
by the Extreme Ultraviolet Imager on board Solar Orbiter, and by the
Atmospheric Imaging Assembly on board Solar Dynamics Observatory. We observed
multiple plasma ejection events over a period of $\sim$1 hour from a dome-like
base that is ca.~4 Mm wide and is embedded in a polar coronal hole. Within the
dome below the jet spire, multiple plasma blobs with sizes around 1--2 Mm
propagate upwards to dome apex with speeds of the order of the sound speed
(ca.~120~km~s$^{-1}$ ). Upon reaching the apex, some of these blobs initiate
flows with similar speeds towards the other footpoint of the dome. At the same
time, high speed super-sonic outflows ($\sim$230~km~s$^{-1}$) are detected
along the jet spire. These outflows as well as the intensity near the dome apex
appear to be repetitive. Furthermore, during its evolution, the jet undergoes
many complex morphological changes including transitions between the standard
and blowout type eruption. These new observational results highlight the
underlying complexity of the reconnection process that powers these jets and
also provide insights into the plasma response when subjected to rapid energy
injection.
