  We present photometric and spectroscopic data for SN 2022joj, a nearby
peculiar Type Ia supernova (SN Ia) with a fast decline rate ($\rm{\Delta
m_{15,B}=1.4}$ mag). SN 2022joj shows exceedingly red colors, with a value of
approximately ${B-V \approx 1.1}$ mag during its initial stages, beginning from
$11$ days before maximum brightness. As it evolves the flux shifts towards the
blue end of the spectrum, approaching ${B-V \approx 0}$ mag around maximum
light. Furthermore, at maximum light and beyond, the photometry is consistent
with that of typical SNe Ia. This unusual behavior extends to its spectral
characteristics, which initially displayed a red spectrum and later evolved to
exhibit greater consistency with typical SNe Ia. We consider two potential
explanations for this behavior: double detonation from a helium shell on a
sub-Chandrasekhar-mass white dwarf and Chandrasekhar-mass models with a shallow
distribution of $\rm{^{56}Ni}$. The shallow nickel models could not reproduce
the red colors in the early light curves. Spectroscopically, we find strong
agreement between SN 2022joj and double-detonation models with white dwarf
masses around 1 $\rm{M_{\odot}}$ and thin He-shell between 0.01 and 0.02
$\rm{M_{\odot}}$. Moreover, the early red colors are explained by
line-blanketing absorption from iron-peak elements created by the double
detonation scenario in similar mass ranges. However, the nebular spectra
composition in SN 2022joj deviates from expectations for double detonation, as
we observe strong [Fe III] emission instead of [Ca II] lines as anticipated
from double detonation models. More detailed modeling, e.g., including viewing
angle effects, is required to test if double detonation models can explain the
nebular spectra.
