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V555 Ori is a T Tauri star, whose 1.5 mag brightening was published as a Gaiascience alert in 2017. We carried out optical and near-infrared photometric,and optical spectroscopic observations to understand the light variations. Thelight curves show that V555 Ori was faint before 2017, entered a high state forabout a year, and returned to the faint state by mid-2018. In addition to thelong-term flux evolution, quasi-periodic brightness oscillations were alsoevident, with a period of about 5 days. At optical wavelengths both thelong-term and short-term variations exhibited colourless changes, while in thenear-infrared they were consistent with changing extinction. We explain thebrightness variations as the consequence of changing extinction. The object hasa low accretion rate whose variation in itself would not be enough to reproducethe optical flux changes. This behaviour makes V555 Ori similar to the pre-mainsequence star AA Tau, where the light changes are interpreted as periodiceclipses of the star by a rotating inner disc warp. The brightness maximum ofV555 Ori was a moderately obscured ($A_V$=2.3 mag) state, while the extinctionin the low state was $A_V$=6.4 mag. We found that while the Gaia alert hintedat an accretion burst, V555 Ori is a standard dipper, similar to the prototypeAA Tau. However, unlike in AA Tau, the periodic behaviour was also detectablein the faint phase, implying that the inner disc warp remained stable in boththe high and low states of the system.

Dipper-like variability of the Gaia alerted young star V555 Ori