Andy, a petro-chemist for an oil company, is urgently called to the Middle East as a global energy crisis begins to unravel. As chaos begins to build in the outside world, Andy becomes more desperate to find answers and reunite with his family.

Andy and Mika arrive at the lab in Luzrah to begin analyzing the samples. As the unrest grows in Europe, Elena decides it's best for her and Sam to go home to London, but with travel severely limited they find that journey increasingly difficult.

Andy makes an alarming discovery about the crisis, but needs daughter's help to confirm his findings. Meanwhile, Elena and Sam are given refuge by an unlikely ally who will offer them a haven and way home...but the trip won’t be easy.

Back in London, Andy is forced to try and prove his innocence by coming up with a solution. While making their journey home, Elena and Sam are detained, and Laura and Owen take shelter in an abandoned boatyard and learn more about each other.

Andy is given an ultimatum, and Tobias pleads his case. Meanwhile, Elena discovers that she and Sam may have been following the wrong lead and she decides that it is time to take matters into her own hands.