Pirates of the Caribbean 4

After Petronella Osgood explained how 'everything' in the UNIT database had been 'heavily corrupted with huge chunks missing', Cleo Proctor joked that it sounded "like my laptop after my brother downloaded that dodgy copy of Pirates of the Caribbean 4". (AUDIO: Recruits)

Behind the scenes
In the real world, the fourth Pirates of the Caribbean film was called.