This movie illustrates the early division up to the four-cell stage of a wild-type C. elegans embryo by DIC microscopy. The first C. elegans embryonic division of the P0 zygote is asymmetric and generates an anterior AB cell, and a smaller posterior P1 cell. These cells have different developmental fates and division timing, with AB dividing approximately 2 min before P1. Additionally, in early C. elegans embryonic cell cycles, S and M phases rapidly alternate without apparent gap phases. The movie corresponds to experiments shown in Fig. 1B and Movie 2 of Mouysset et al. Movie is CIL 25629 and original data file is CIL 35124.