Not so much "Indiana Jones And The Temple of Cthuthu" as some have suggested, more "Commando v Cthulhu," this is superior LitRPG following the rip-roaring adventures of the enigmatic Captain/Major/Mr Seraph during WWII and the Napoleonic era.
The stories are very much in the spirit of the old Commando comics, with sturdy, reliable Tommies, posh but heroic officers and diabolical Nazis. Weaponry is in the forefront and the action is lit up with dramatic shootouts with Sten guns against MP40s and a few grenades for good measure. But this sort of weaponry is limited against the real enemy: terrifying paranormal beings which can only be countered by the forces which Seraph can (just about) bring to bear.
One of the stories, featuring the dashing French hussar Gaston Dubois, is set in the Peninsular War, and while the accents change, the spirit is the same, but this time with added galloping hooves and flashing blades. (Dubois sometimes speaks like a character out of 'Allo 'Allo which can be distracting but it does help his character shine through).
Houlihan has does his research and it shows, with an impressive spread of period details. These are historical worlds you can wander around and sit down in, full of nice touches rather than the usual two-dimensional backdrops. If the plots are somewhat linear, that is a feature of the genre, and the villains and monsters are suitable villainous and monstrous, not to say larger-than-life.
An enjoyable set of tales which will help establish Seraph as a fixture in the Mythos world -- and a very useful ally for those in need.