1969: on a mission to photograph a Russian installation, Travis Morgan of the US Air Force falls through a hole in the North Pole and ends up in a strange world of adventure: Skartaris! He rescues a beautiful girl from a dinosaur, falls asleep a day - or is it twenty years? - and wakes up with the iconic white beard. He leads a great revolt against the evil Deimos, but that's only the beginning of his adventures...
The stories are very derivative of Conan, but one important element of that series is missing here: Grell's women aren't half as attractive as Buscema's. It has some interesting elements of its own, though, in particular the unruly operation of time in Skartaris, with days and years flashing by in the blink of an eye, and the remains of Atlantean technology Morgan slowly uncovers. One other difference is Morgan's pistol, giving him a tactical advantage over the locals - as long as the bullets last.
Morgan himself is an interesting character, presented as a hero, but also on occasion a cold-blooded murderer (p. 189 and p. 230). Though a more-or-less modern man, he is also given to fits of frenzy - he isn't a calm, trained fighter, but rather one who "erupts with the blind fury of a berserker". Nowadays our action heroes are Jack Bauer, Jason Bourne, Daniel Craig's Bond, people who fight with precision, intelligence and control. Different heroes for different times, perhaps.
This series takes an unusual approach to gravity - the idea is that the entire Earth is hollow, and gravity emanates from the Earth's crust, so that the people of Skartaris walk around on the inside of the Earth's surface, just as we walk around on the outside. The effect is that Skartaris is huge, a surface area almost equal to that of Earth, as opposed to just a big area inside a cave. It's not clear from these stories why the other side of Skartaris isn't visible across the sky, though I expect it came up in the letter-columns.
It's not a patch on Conan, but it's a decent men's adventure story. If a little clumsy at times, the artwork is ambitious and bursting with violent energy. The serial nature of the story, and the creative consistency (Grell writes and pencils every issue), makes the book very readable, and there's no messing about - it's all action, all the time. Nothing earth-shattering, but a pleasure to read.