Ghost Chasers - Season 1 Episode 3 Harwich

The team investigate paranormal activity in one of Britain's most famous port towns, Harwich. In a haunted lighthouse, psychic Ian picks up on the disaster of the HMS Gipsy, a World War 2 destroyer that was sunk nearby with the loss of many men. Later the team investigate a military fort known as the 'Redoubt', once used to imprison condemned sailors awaiting execution. Things take a dark twist when somehow Kay and the team become locked into one of the cells. Is this the work of a malevolent poltergeist?