After widening its lead as the No. 1 cable series of all time, The Walking Dead has skyrocketed again, thanks to DVR viewers.

With an already incredible 16.1 million viewers this past Sunday night, the AMC zombie thriller's season four premiere gained an additional 4.1 million via DVR, according to the newly released "Live+3" ratings (live viewership combined with those watching within three days of the original airing).

As DVR viewing continues to be the norm, most networks generally factor in that three-day grace period.

As we previously reported, Dead had already claimed the title of most-viewed cable series of all time with 12.4 million viewers for its season three finale. But these new numbers only further elevate it above its competitors.

Of its new season premiere viewers, a staggering 10.4 million (13.2 million counting Live+3) were in the highly coveted 18-49 demographic, more than any NFL game this season.

With an 8.3 rating in that key demo, that's significantly more than even heavy hitter Big Bang Theory, which had a then-satisfying 6.1 rating for its premiere night last month. NCIS (which, by contrast, airs on broadcast network CBS) is currently the top show on TV with an average of 20 million viewers watching live.