The fastest way to produce genetic novelty in a Red Queen host-parasite arms race may be the rapid production of new sequence or gene combinations by recombination. In a hybrid zone recombination across taxa can make production of novel (re)combinations even richer, and their detection (due to previous divergence) easier. We propose the house mouse hybrid zone (HMHZ) and the murine cytomegalovirus (MCMV) as an ideal system to study such dynamics and test the predictions of the recently published Red Queen Recombination model. The HMHZ is the best understood secondary contact species barrier in nature; MCMV is the laboratory mouse model for its human equivalent, and so MCMV ecology and molecular biology are well described; its genome of ~170 genes is easy to study and sequence in its entirety (at ~230 kb). Combined with Next Generation tools available for the mouse host, the HMHZ/MCMV study system will allow us to quantify the ability of a virus to capture genes enabling it to cross a species barrier, and of its host to respond by incorporating alternative defence variants.