  We present the analysis of Multi-Espectr\'ografo en GTC de Alta Resoluci\'on
para Astronom\'ia (MEGARA) high-dispersion integral field spectroscopic
observations of the bipolar planetary nebula (PN) M 3-38. These observations
unveil the presence of a fast outflow aligned with the symmetry axis of M 3-38
that expands with a velocity up to $\pm$225 km s$^{-1}$. The deprojected space
velocity of this feature can be estimated to be $\approx$320$^{+130}_{-60}$ km
s$^{-1}$, which together with its highly collimated morphology suggests that it
is one of the fastest jet detected in a PN. We have also used Kepler
observations of the central star of M 3-38 to unveil variability associated
with a dominant period of 17.7 days. We attribute this to the presence of a
low-mass star with an orbital separation of $\approx$0.12-0.16 au. The fast and
collimated ejection and the close binary system point towards a common envelope
formation scenario for M 3-38.
