According to Nerve Software boss Brandon James the expansion set "continues on Earth after Hell's forces have [seemingly] been vanquished".
The goal of the expansion is to travel to a pocket dimension of Hell and assassinate a Cyberdemon that has been building an army of demons for his own personal use. No Rest for the Living takes advantage of the expanded capacity of modern systems, with significantly more enemies on-screen at the same time than in the original Doom 2, especially in the later levels.
