Neptune King and the Gallant Thief is the 23rd and latest book in the Neptune King series. A charity function that the Kings are attending is robbed by a dozen shotgun wielding men led by a charismatic character calling himself Robin Hood. Robin makes an exception of Neptune and Rachel by not robbing them, citing their generosity to an old beggar outside the venue as his reason. At first Neptune is disinclined to go after him, especially when he learns that Robin is actually giving the proceeds to the poor, and even has a grudging admiration for the man for his proficiency in the art of disguise. However when aspersion is cast on his reputation and comments are made that he wasn't robbed because he was connected to Robin, he realizes he has no choice but to catch the thief for the sake of his business and reputation. Using his own considerable skills he goes in under cover to the East End as an elderly vagrant and soon picks up some information on Robin and his gang. He also learns that Robin is perhaps not quite as altruistic as he appears, as the poor are only receiving a very small percentage of the take. When one of Robin's men is found dead after casting doubts about Robin's integrity and motives, Neptune is even more determined to apprehend him. Neptune and Milo Washington (their employee in charge of insurance investigations) infiltrate Robin's gang, while Shark, with the help of his dog, Fang, set about recovering the missing jewels. Together, they set a trap for Robin, once again showing why K & J Investigations is not a firm to messed with.