During the Chimeran invasion of the United Kingdom, Dexter, alongside the Royal Marine Commandos were placed under the tactical control of the British Intelligence Corps. Waging a guerilla war against the Chimeran occupiers, the Commandos served as the major reconnaissance unit for the British Army. During this time, Dexter's unit encountered increasing Cloven forces during their patrols.
Sometime on July 10th, 1951, Dexter requested the assistance of a British medical officer to follow the commando unit as they investigated the sudden appearances of Cloven corpses. Inquiring over the sudden request, Dexter remained unwilling to provide specific details to the medical officer. Nevertheless, the unit discovered the appearance of more Cloven bodies, as the medical officer examined the corpses, he noted that aside from the uniform, the distinct lack of skin proved even more disturbing, suggesting that similarly to the Chimera, the dead Cloven had been resorting to cannibalism.