Trying to keep the click of their heels on the cobbles to a minimum, the women sneaked into the shadowy entranceway directly opposite Marsden’s rooms. The last of the light had faded. It was ten o’clock. All over Cambridge, church bells were striking. Two students parked their bikes and disappeared with a clatter into a building further along. The porter, now wearing an old-fashioned cape, set out on his rounds, checking the library door and making sure the gates in the railings that skirted the campus were locked and chained. Out of habit, Mirabelle timed him. The accommodation blocks, unlit for the most part, were completely silent. A fox stalked elegantly between the rows of potatoes and disappeared through the railings at the other end. Vesta sighed and wriggled around on the bottom step of the stairway. She rested her chin in her palm. It had perhaps been half an hour but, Vesta thought, it seemed considerably longer. ‘This isn’t promising,’ she complained. ‘Nothing’s happening.’ ‘Surveillance is always boring,’ Mirabelle replied.