Wren awakes in a present day in which World War 1 never ended, and the alternative him died as a child. Somehow, his nightmares entered the dreams of Carina, a girl on board the Titanic. Using Wren's knowledge, she has been able to avert the tragedy, so creating a ripple in time. With the help of Carina's descendant, Carrie, Wren must find a way to go back and restore the time line. If he does, the lives of those aboard the vessel will be lost, and the love of his life will never be born.
Will he be able to save the present, or is history as we know it doomed?
"A Ripple in Time" is the second Celtic Cousins' Adventures; preceded by "A Raucous Time" in which the cousins are on the trail of an ancient mystery, while the third title "An Explosive Time" is set in London, and features the long suffering DI Crombie, a disappearing elephant, and an alligator addicted to fish – and chips.