Originally published in eight parts between January and February 1972, *Sub Zero (the asterisk is part of the title) is a comic strip written by Dennis Hopper and illustrated by Gerry Haylock. It first appeared in Countdown and also in DWCC 5, before making a recent appearance as a free gift in DWM 208. As you can see from the cover it is a Third Doctor adventure about atomic submarines and Daleks! So, decades before Cold War we have the Doctor and submarines!
As a story it has its flaws and is rather of its time. The Doctor is called Dr. Who, and is randomly visiting a US weather station in Antarctica before encountering yet another Dalek plot. For the most part the story could be almost any villain, and the Doctor is more action hero than Time Lord, though there are many tropes: the Daleks recognise their enemy and are also intent on converting humanity to Dalek form. As a piece of entertainment it is OK, but other than that is largely disposable. Their is no UNIT, no companion, no TARDIS, Bessie or even a sonic screwdriver to be seen!