It's 1971 in Hampshire in south east England. 13 year-old Thomas Trilby is set to enjoy his summer holidays. Unaware that a treacherous plot is unfolding in a nearby underground bunker, Thomas and his friends are thrust into a world fraught with danger. A stolen, priceless sapphire, a handful of the most vicious Russian mobsters, a kidnapped friend, and with his beloved Granddad violently hospitalized, Thomas will need his wits about him to survive. A harrowing motorcycle journey through the dark and foggy countryside of England and Scotland on his Granddad's old Royal Enfield Bullet. A gothic castle, containing a hideous madman, and a beautiful girl, send Thomas and his friends into international waters, where the stakes could not be higher.