Tense drama series about the different challenges faced by the British Security Service as they work against the clock to safeguard the nation. The title is a popular colloquialism for spies, and the series follows the work of a group of MI5 officers based at the service's Thames House headquarters, in a highly secure suite of offices known as The Grid.

Four teenagers at a British private school secretly uncover and explore the depths of a sealed underground hole created decades ago as a possible bomb shelter.

Instead of spending her golden years lying down, the indomitable Hetty Wainthropp found her calling late in life. Combining common sense, her husband, and her pocketbook, this senior sleuth takes on all the cases the police deem too minor.