The first identified giant virus retained by the Chamberland filter, was called "Mimivirus" in 2003. With a particle of 0.7 micrometer in diameter packing a 1.2 Mb genome encoding 979 proteins, Mimivirus was the first virus overlapping the world of bacteria both in terms of particle size and genome complexity. These giant viruses are not rare and many Mimivirus relatives were then quickly isolated, culminating with Megavirus chilensis, encoding 1,120 proteins among which 7 aminoacyl-tRNA synthetases, until then considered hallmarks of cellular microorganisms. As we thought we were finally reaching the limit of viral complexity and started to build a new paradigm about the evolution of DNA viruses, the discovery of the Pandoraviruses came ruining this newly built theoretical edifice. With 1.2 micron-long particles packing a genome of 2.5 Mb encoding more than 2,500 proteins, Pandoravirus salinus is now surpassing the complexity of the smallest eukaryotic cells, such as parasitic microsporidia species. However, with less than 10% of their predicted proteins resembling anything, as well as their unique mode of replication, the Pandoraviruses clearly represent a class of giant viruses totally unrelated to the Megaviridae. Finally, I will present the discovery of Pithovirus sibericum, isolated from a >30,000-y-old radiocarbon-dated sample of Siberian permafrost. This third type of giant virus combine an even larger pandoravirus-like particle 1.5 μm in length with a surprisingly smaller 600 kbAT-rich genome, a gene content more similar to Iridoviruses and Marseillevirus, and a fully cytoplasmic replication reminiscent of the Megaviridae. Pandoravirus-like particles may thus be associated with a variety of virus families more diverse than previously envisioned. To conclude, I will briefly present the hypotheses that have been proposed about the origin and evolution of DNA viruses and their possible link with the emergence of eukaryotes.