Originally self-published, Alexander Darwin’s THE COMBAT CODES (out now, Orbit) is set in a world where the fate of empires is determined by warriors trained to compete in brutal single combat. (Funnily enough, we decide who’s writing the next quiz page in similar fashion.) A rescue mission leaves a team of US soldiers, rescued hostages and a prisoner trapped in a suborbital craft in John Shirley’s near-future thriller SUBORBITAL 7 (out now, Titan), which we’re told should appeal to fans of Tom Clancy and his ilk. A siren assassin’s investigations into a blackmailer threatening her sister lead her to become personal bodyguard to the Crown Prince in Gabi Burton’s YA fantasy SING ME TO SLEEP (Hodder, 27 June). The latest Doctor Who/ Puffin Classics crossover (after stories featuring King Arthur, Oz and Robin Hood) is REBELLION ON TREASURE ISLAND (22 June, BBC Children’s Books). Bali Rai’s adventure sees the Eleventh Doctor and Clara investigating a theft from the Crown of King George. Long John Silver and River Song are both along for the ride… Turning to continuing series: there’s a follow-up to Her Majesty’s Royal Coven, Juno Dawson’s book about a covert government department: THE SHADOW CABINET (HarperVoyager, out now). Insert political joke here. Finally, Robert Jackson Bennett’s inventive Founders trilogy – set in a world where criminals use a sciencey magic called “scriving” to fool objects into acting contrary to the usual rules of physics – ends with third volume LOCKLANDS (out now, Jo Fletcher Books).