This is the first in Simon Hawke's 12 "Time Wars" novels about a crack team of time travelling agents.
It kicks off a humorous and well written series about a group of operatives who travel through time to prevent other time travellers from causing damage to history.
Sometimes, as in this book, their opponents are rogue individuals or groups of terrorists who are trying to subert the past for their own purposes: sometimes they come up against operatives from rival alternative futures who are trying to defend their own versions of history.
All 12 books in this series pay humorous homage to a great work of literature, to a set of historical events, or both. Most of these books go back to the time and events of a classic novel, in this case, obviously, "Ivanhoe" by Sir Walter Scott, and revisit the events of that novel, usually with a humorous slant.
The books are best read in the correct sequence, as follows (I have put the name of the literary work and/or historical events associated with each book in brackets afterwards)
1) The Ivanhoe Gambit (Ivanhoe)
2) The Timekeeper Conspiracy (The Three Musketeers)
3) The Pimpernel Plot (French Revolution & terror/Scarlet Pimpernel)
4) The Zenda Vendetta (The Prisoner of Zenda)
5) The Nautilus Sanction (20,000 Leagues Under the Sea)
6) The Kyber Connection (works of Rudyard Kipling/early life of Churchill)
7) The Argonaut Affair (Jason and the quest for the Golden Fleece)
8) The Dracula Caper (Sherlock Homes meets Bram Stoker's Count Dracula)
9) The Lilliput Legion (Gulliver's travels)
10) The Hellfire Rebellion (American War of Independence/Hellfire Club)
11) The Cleopatra Crisis (Caesar and Cleopatra)
12) The Six-gun solution (Gunfight at the OK Corral)
Not terribly serious but very good fun: I can recommend this series, and if you want to read it, start with this one.