During meiosis, completion of homologous recombination and disassembly of the synaptonemal complex (SC), which facilitates chromosome synapsis, must be coordinated during the prophase to metaphase I (G2/MI) transition to avoid the formation of aneuploid gametes. Kinase activity promotes exit from meiotic prophase, but exactly which kinase triggers SC disassembly, the first step in the G2/MI transition? On page 5061, Mary Ann Handel and co-workers implicate polo-like kinases (PLKs) in this process in mouse spermatocytes in vivo and during exit from prophase, which has been induced ex vivo by the phosphatase inhibitor okadaic acid (OA). The authors report that all four kinase-proficient mouse PLKs are expressed during the first wave of spermatogenesis, but that only PLK1 localises to the SC during the G2/MI transition. They show that several SC central element proteins, including synaptonemal complex protein 1 (SYCP1) and testis expressed protein 12 (TEX12), are phosphorylated during the G2/MI transition, and that PLK1 phosphorylates SYCP1 and TEX12 in vitro. Moreover, the PLK1 inhibitor BI 2536 impairs the phosphorylation and removal of central element proteins from the SC and inhibits OA-induced exit from meiotic prophase. Thus, the authors suggest, PLK1-mediated phosphorylation is required for the first stage of SC disassembly in mammalian spermatocytes.