Ever since the accident, Tom's struggled with his mobility. But he has a secret escape: Skylark, his drone—through this technology, he can fly above his Lake District home, exploring his world from a totally different perspective. But when he stumbles upon a terrorist plot, he knows no one will believe him. Maggie and Joel, a sister and brother on holiday in his aunt's cottage, are the only ones who can help... but can they stop the plot in time?