To recreate conditions similar to those of the early universe, powerful accelerators deliver head-on collisions between massive ions, such as gold or lead nuclei. In these heavy-ion collisions the hundreds of protons and neutrons from these nuclei smash into one another at energies of upwards of a few trillion electronvolts each. The extreme energy density that is then reached causes the formation of the quark-gluon plasma. The QGP quickly cools until the individual quarks and gluons recombine into a blizzard of ordinary matter that speeds away in all directions. The ALICE detectors are designed to efficiently detect the particles produced in such lead-lead collisions at the LHC.