How does the author use foreshadowing in Enigma?

Both Jericho and Kramer lost close relatives in World War I. This ties them together for a common purpose. At the start, they are very different people. Kramer is thoughtful and careful. Jericho is nearly insane and undermines the authority. This creates a relationship where both need the other, and it foreshadows that Jericho and Kramer may be working together closely in the future to crack the code and get to the truth of the British navy.