Sigma Force roars back into action after a startling discovery: a medieval seagoing vessel buried deep under the Greenland ice that contains a mysterious globe that appears to chart Odysseus' last voyage, including the path under the sea to the mythical Gates of Hell. Could an underground river beneath the Mediterranean Sea actually exist? A megalomaniac is determined to use the secrets stored aboard the buried ship to change the world according to his own twisted dreams, and it's up to Sigma Force, the globe-trotting, troubleshooting arm of the Department of Defense's DARPA, to stop him--even if it means going to where no mortal has gone. Rollins is one of those writers whose name assures certain guarantees. You know you'll be treated to lots of slam-bang action, larger-than-life heroes and villains, snappy dialogue, and a plot that stretches credibility almost to the breaking point. Like Matthew Reilly, who writes novels in a broadly similar vein, Rollins is a master of the genre, able to sweep us up and carry us along until he brings the story to a riveting conclusion.

Bestseller Rollins's excellent 15th Sigma Force novel (after 2018's Crucible) marries nail-biting action with a highly imaginative premise. Elena Cargill, an archaeologist and paleoanthropologist, rushes to Greenland at the behest of a friend, Maria Crandall, who's a member of Sigma, a U.S. government organization that retrains gifted soldiers in various scientific disciplines. Crandall has learned of an amazing find beneath a giant iceberg--an Arab oceanic merchant vessel, apparently shipwrecked in the ninth century. Cargill and two colleagues visit the ship, in which they discover such wonders as a three-dimensional gold map embedded with an astrolabe, before coming under attack from a group of Middle Easterners, who take Cargill hostage. Crandall and other Sigma Force members later embark on a mission to save Cargill and understand the significance of the vessel, which may be connected with the historical basis for Homer's Odyssey and a lost nation that destroyed three major civilizations between 1100 BCE and 900 BCE. Rollins sprinkles in enough facts and details to make what could have been an over-the-top premise plausible. This is a thoughtful, nonstop thrill ride that's an exemplar of an escapist page-turner. Author tour. Agents: Russ Galen, Scovil Galen Ghosh Literary Agency; and Danny Baror, Baror International. (Mar.)

A half mile beneath the frozen (if melting) tundra of (not-for-sale) Greenland, archaeologists find a medieval ship whose hold contains Bronze Age artifacts, including a clockwork gold atlas ringed by silver astrolabe crafted by a Muslim inventor named Ismail al-Jazari who inspired Leonardo Da Vinci. The moving globe reveals Odysseus unexpectedly following an underground river to dark Tartarus (that's ancient Greek for hell), and now the entire war- and terrorist-ridden region is in an uproar, which puts Sigma Force front and center. With a 350,000-copy first printing.

Inferno with rocket launchers and astrolabes: Rollins (Crucible, 2019, etc.) takes his readers to hell.You're making a mistake if you approach a Rollins novel without suspending every ounce of disbelief that you hold. Otherwise, who would swallow a hook baited with the premise that, by way of the ancient Homeric epics, modern jihadists are on the verge of leveraging the supernatural powers of the underworld, following the footsteps of a shadowy cabal, which, as Pope Leo X tells Leonardo da Vinciyes, that Leonardo da Vincionce upon a time "found the entrance to Hell"? It's up to the good guys of Sigma Force, the secret and highly lethal special-ops division of the Defense Advanced Research Projects Agency, to save the world from such malign possibilities. As always, Cmdr. Gray Pierce and company perform superhuman feats in the service of truth, justice, and the American way, with some sympathetic and highly capable civilian in tow. In this case, it's a scholar named Elena Cargill, who, apart from holding "dual PhDs in paleoanthropology and archaeology," is also the daughter of the chair of the U.S. Senate Committee on Foreign Relations, making her an attractive target indeed. As we meet her, Elena is working through an archaeological puzzle: How did the Arabian super-dhow that she's discovered under hundreds of feet of Greenlandic ice get there? It might just have something to do with a clockwork mechanism that steers interested parties toward the flaming depths of Tartarus and its resident demons, titans, metal mastiffs, and their ilk. You'd think it no place to visit, but it'd be handy to have such tools in one's kit if one were bent on world conquest. So it is that Elena and the DARPAnauts go up against a nefarious band of terrorists, one a James Bond-worthy giant and the other, this being equal-opportunity evil, a smart and ever so ill-tempered woman who "savor[s] the kill to come" and wreaks an awful lot of damage, as supervillains will. Mayhem ensues.Improbable and sometimes silly, but Rollins spins an entertaining thriller out of a long string of what-ifs. Copyright Kirkus Reviews, used with permission.