Personally, I am getting sick of all the drippy romantic vampire drivel that was churned out because of the now-dead "Twilight" craze. 
 So it's something of a relief to come across a book like "Blood Oath," which instead focuses on a really cool concept -- what if there were a vampire secret agent who had been serving the US president for the last century-and-a-half? "Blood Oath" at times feels like a paint-by-numbers thriller, but the fast pace, solid prose and inclusion of vampire intrigue make it a fun read. 
 Zach Burrows is an ambitious, fast-rising young political figure... until he's caught fooling around with the president's teenage daughter. So he's reassigned to a new post: the presidential liaison to Nathaniel Cade, a vampire who is blood-oathed to the president, and who does all sorts of secret missions to destroy supernatural threats to the United States. 
 Their first mission: jihadist terrorists are shipping dismembered American soldiers into the U.S., intending to create Unmenschsoldat -- undead killing machines, better known as Frankenstein monsters. 
 So Cade and the reluctant Zach are sent to find the one man who can create those monsters, but are unable to prove anything. Even worse, they have attracted hostile attention from several different areas -- the monstrous Dr. Konrad, a beautiful vampire, and a terrifying Shadow Company which knows no mercy. They're determined to bring down the United States, even the world as we know it... and Cade too. 
 It doesn't come as a surprise that Christopher Farnsworth is a screenwriter, because "Blood Oath" reads like the novelization of a fast-paced action thriller. It has some well-placed flashbacks, evil terrorists, flashy political conspiracies, and a sort of James Bond vampire (minus the girls) -- even the action-packed opener feels like the teaser to a movie, right before the opening credits. 
 The biggest flaw in the book is that sometimes it feels a little too by-the-numbers as an action thriller. However, it's also lots of fun -- Farnsworth blasts through a fast-moving plot, and fills the pages with plenty of action, horrific gore and snappy dialogue ("Someone has to protect the meek until they can inherit the Earth"). Compared to all that soppy "Twilight" drivel, Farnsworth's prose has a sleek masculine tang that's very refreshing. 
 He also inserts lots of pseudoscientific/pseudohistorical snippets from classified files, deftly fleshing out the whole idea of a presidential vampire. Plus, he inserts some clever nods to H.P. Lovecraft and Chelsea Quinn Yarbro. 
 And Cade is very chilly and introverted, but also very capable and intelligent. Despite believing that he's eternally damned, he's also a creature of strong morals and rock-solid beliefs. Farnsworth does an excellent job depicting a man of the mid-1800s who has grown and changed over the centuries, even if he has the quirky habit of using outdated slang. Zach is an annoying little twerp at first, but becomes more likable over time. 
 "Blood Oath" follows the mold for action thrillers, but adds in plenty of supernatural chills and vampiric problems. Here's hoping for more stories to come.