Three weeks before Christmas, MI7 has credible evidence that there is a potential security breach at Kensington Palace and thus a threat on its residents: Princess Rose, first in line to the throne, her military husband Prince Edward who is away on a secret mission and thus may not make it home for Christmas, and their two adolescent offspring, second and third in line Princess Elle and Prince Robert. Taylor, the head of MI7, wants to insert agents working on the file undercover into the palace without the royal family being aware of the potential threat against them, the only two available positions being Protection Officer, assigned to Agent Wallace, and Royal Nanny, assigned to Agent Claire Champion. Claire does not believe she the best person for this specific undercover assignment in knowing nothing about children and raising such in a nurturing environment having been raised in an orphanage herself and having no children of her own or in her life, something to which MI7's case specific advisor Juliet Lansbury concurs, she who has trained and provided the nannies for the royal family for a generation. With no other agent as an alternative, Mrs. Lansbury has twenty-four hours to train Claire, who will go by the name Claire Carter, to be the proper nanny, the end goal, both as a nanny and as an MI7 agent, to protect Princess Elle and Prince Robert at all cost. Claire will discover that the biggest threats against her as a person are her charges, who have taken it upon themselves to prank their previous nannies to the point of they wanting to quit. The Princess and Prince have as their biggest ally their uncle, Princess Rose's younger brother, fourth in line Prince Colin, who does not live at the palace but visits frequently, he the head of the royal family's Christmas charity of providing toys to children at orphanages. Beyond the issues with the Princess and Prince which relates directly to Princess Rose's self assessment that she wants and needs to be a more present part of her children's lives, difficult with all her royal duties, Claire has the difficulty of dealing with Prince Colin in those nanny/agent duties. In spending time with them, Claire is able to break down the defenses of her two charges and their uncle, Claire and Colin who seem to be falling for each other. A problem arises when Taylor receives further evidence that Prince Colin himself may be that threat against the royal family, his own family.
