  HIZSS3 is an H I source in the Zone of Avoidance. Its radio characteristics
are consistent with it being nearby (~ 1.8 Mpc) low-mass dwarf irregular (dIm)
galaxy. It contains a modest H II region, but its stellar population has not
been resolved by optical observations. MMT spectra of the H II region are used
to derive the line-of-sight extinction (E(B-V) = 1.41 +/- 0.04) and gas
metallicity (log O/H + 12 ~ 7.8). ESO VLT near-IR images clearly reveal a
resolved stellar population. Narrow-band Pbeta images of the H II region are
used in combination with previously published Halpha data to obtain an
independent line-of-sight extinction estimate: E(B-V) = 1.32 +/- 0.04. The
adopted foreground extinction is E(B-V) = 1.36 +/- 0.06. Based on the K-band
luminosity function and K,J-K color-magnitude diagram, the apparent magnitude
and color of the tip of the red-giant branch (TRGB) are derived. In turn, these
parameters are combined with the adopted foreground extinction to estimate the
distance (1.69 +/- 0.07 Mpc) and mean red giant branch metallicity ([Fe/H] =
-0.5 +/- 0.1). As an ensemble, these new observations significantly strengthen
the conclusion that HIZSS3 is a newly discovered low-mass dIm lurking behind
the Milky Way in the outskirts of the Local Group.
