Ambitious and abandoned is how I would describe this graphic novel. The premise of this short-lived Marvel series was that S.H.I.E.L.D., the spy organization founded after WWII to hunt down Communists and other insurgents, is actually a ancient secret society which has defended the Earth from alien threats since at least 2620 BC. Every famous scientist, artist, or mystic you can think of was a member, including Da Vinci, Galileo, Isaac Newton, Nostradamus, and Nikola Tesla. More modern members include Howard Stark, the father of Tony (Iron Man) Stark, and Nathaniel Richards, the father of Reed (Mr. Fantastic) Richards.
The plot jumps all around and throws in all manner of twists including a war between immortals Newton and Da Vinci over the fate of humanity, a time traveling Tesla who is married to a woman who can turn into a bird (or something), a Chinese scholar named Zhang Heng who hid a baby Celestial, and lots of vague references to ominous sounding things like the Greater Science, the Hidden Arts, and the Human Machine.
It all seems very promising, and Dustin Weaver's illustrations are excellent, but it appears not to have been the hit Marvel hopped it would be and the project was quietly abandoned. Hickman has occasionally dropped references to the deep history of S.H.I.E.L.D. in his other Marvel work, suggesting his has not given up on the idea, but we will probably never see a continuation of the series big enough to do justice to the scope of the premise.