This ancient and crumbling castle invokes the troubled maritime and smuggling history of Cornwall. It is said to be built on the site of a Tudor Manor around 1500. The grounds include a large wooded area with ruins that play host to ghost sightings of sailors and monks. This is an atmospheric location that spooks even the hard-bitten, worldy-wise Most Haunted crew. The castle is at the centre of many myths and legends, one of which is that Henry Pengersick was violent man and that back in the 12th Century he killed a monk and wounded a vicar. The present owners believe that if there are ghosts at Pengersick Castle they could be of Henry Pengersick, later known as Henry Le Fort and his wife Engrina. Another legend is that of an evil man who left his wife while fighting in foreign lands. While on his travels he courted another woman who gave him a magic sword. He returned to his castle to have his wife and young child drowned and to marry yet another woman, this one an evil witch. His other son, who survived, years later rescued a drowning sailor who turned out to be his brother left for dead at sea. This tale steeped in local folklore accounts for many of the said hauntings at Pengersick Castle.

The investigation begins on the battlements where Derek connects with the spirit of a young girl who he feels had fallen over the edge. He also senses her apprehension for a man named John who can be found on the lower levels. Moving to the Solar Room he sees a Monk standing in the doorway pointing at the floor, suggesting a murder took place here, while he also picks up on a little boy called Jamie Godolphin. He then requests a break as he begins to feel a choking sensation, at which point Richard is forced to leave the room as he too finds it hard to breath. Upstairs in the bedroom Derek connects with the energies of 2 young ladies, both of whom he felt were murdered here, however he then moves suddenly to the fireplace suggesting that a demon creature crouches here, once summoned by the evil John Milliton, who practiced the dark arts. At this point both Yvette and Phil hear a noise by their feet which cannot be explained. Moving outside Derek picks up on unconverted burial ground where he feels many souls are buried, some of whom were the sacrificial victims of witchcraft. As the vigils begin, 2 groups make their way outside to stay in tents pitched on the burial ground. Both Rick and Craig as well as Cath and Victoria hear movement and rustling outside the tents. Meanwhile in the Solar Room Yvette, Derek and Phil hear a door banging from below, and investigating they notice a door at the bottom of the stairs ajar. At that point the door suddenly slams by itself, and no wind or breeze was present. Later Yvette also picks up an orb and a strange flashing light anomaly. The investigation concludes bizarrely, as Rick and Karl experience running steps in the gravel directly behind them as they are about to enter the castle.