  V555 Ori is a T Tauri star, whose 1.5 mag brightening was published as a Gaia
science alert in 2017. We carried out optical and near-infrared photometric,
and optical spectroscopic observations to understand the light variations. The
light curves show that V555 Ori was faint before 2017, entered a high state for
about a year, and returned to the faint state by mid-2018. In addition to the
long-term flux evolution, quasi-periodic brightness oscillations were also
evident, with a period of about 5 days. At optical wavelengths both the
long-term and short-term variations exhibited colourless changes, while in the
near-infrared they were consistent with changing extinction. We explain the
brightness variations as the consequence of changing extinction. The object has
a low accretion rate whose variation in itself would not be enough to reproduce
the optical flux changes. This behaviour makes V555 Ori similar to the pre-main
sequence star AA Tau, where the light changes are interpreted as periodic
eclipses of the star by a rotating inner disc warp. The brightness maximum of
V555 Ori was a moderately obscured ($A_V$=2.3 mag) state, while the extinction
in the low state was $A_V$=6.4 mag. We found that while the Gaia alert hinted
at an accretion burst, V555 Ori is a standard dipper, similar to the prototype
AA Tau. However, unlike in AA Tau, the periodic behaviour was also detectable
in the faint phase, implying that the inner disc warp remained stable in both
the high and low states of the system.
