Moran, aka one of the creepy ghost dudes from the underwater base in Under The Lake and Before The Flood, was played by Colin McFarlane, which wasn't the first time he has appeared in the Who universe. He voiced a character in the 2007 Christmas Special Voyage of the Damned, while he also appeared as General Pierce in the spectacular Torchwood: Children of Earth series. Unlike with another actor to have appeared in Who and Children of Earth before playing yet another character on Doctor Who, there probably isn't any link between all of McFarlane's characters. Unless there is. Let the theorising commence.