Edge of Danger — Jack Higgins

For hundreds of years, the Rashid has flourished. Now, endowed with a mix of sturdy British and fiery Arab bloodlines, they have become a remarkable family of warriors--equally at home in the streets of London or under the desert sun. And now they have a vendetta to settle. The object of their wrath--the president of the United States.

Across the globe, hints of the coming violence are picked up by Blake Johnson, head of the secret White House operation known as The Basement, and his colleague, ex-IRA enforcer Sean Dillon. But when will the enemy strike? And why have they vowed to die rather than surrender? Frantically, Blake and Sean hunt to find the answers before it's too late for the president--and the world...