  We present the properties of the recently discovered class of variable stars,
Blue Large-Amplitude Pulsators (BLAPs). These extremely rare, short-period
pulsating objects were detected thanks to regular, high-cadence observations of
hundreds of millions of Milky Way stars by the OGLE variability survey. The new
variables closely resemble classical pulsators, Cepheids, and RR Lyrae-type
stars, but at effective temperatures at which pulsations are due to the
presence of iron-group elements. Theory shows that BLAPs are evolved low-mass
stars with a giant-like structure, but their origin remains a mystery. In this
contribution, we report the negative result of a search for BLAPs in the whole
Magellanic System.
