Question: Third Murderer appears to assassinate someone in legendary Scottish history known as what?

Context articles: The Frighteners
Dauvit Broun
Scáthach
Fleance
Innes Review
Arson in medieval Scandinavia
Third Murderer
Highland Potato Famine
Edward J. Cowan
Michael Lynch (historian)

The Frighteners is a 1996 New Zealand-American horror comedy film directed by Peter Jackson and co-written with his wife, Fran Walsh.
 The film stars Michael J. Fox, Trini Alvarado, Peter Dobson, John Astin, Dee Wallace Stone, Jeffrey Combs, R. Lee Ermey and Jake Busey.
 "The Frighteners" tells the story of Frank Bannister (Fox), an architect who develops psychic abilities allowing him to see, hear, and communicate with ghosts after his wife's murder.
 He initially uses his new abilities to befriend ghosts, whom he sends to haunt people so that he can charge them handsome fees for ""exorcising"" the ghosts.
 However, the spirit of a mass murderer appears able to attack the living and the dead, posing as the ghost of the Grim Reaper, prompting Frank to investigate the supernatural presence.
Dauvit Broun, FBA (English: David Brown ) (born 1961) is a Scottish historian and academic.
 He is the Professor of Scottish History at the University of Glasgow.
 A specialist in medieval Scottish and Celtic studies, he concentrates primarily on early medieval Scotland, and has written abundantly on the topic of early Scottish king-lists, as well as on literacy, charter-writing, national identity, and on the text known as "de Situ Albanie".
 He is editor of the "New Edinburgh History of Scotland" series, the pre-1603 editor of the "Scottish Historical Review", convener of the Scottish History Society, and the Principal Investigator of the Arts and Humanities Research Council-funded project 'The Paradox of Medieval Scotland, 1093-1286'.
Scáthach (Scottish Gaelic: "Sgàthach an Eilean Sgitheanach" ), or "Sgathaich", is a figure in the Ulster Cycle of Irish mythology.
 She is a legendary Scottish warrior woman and martial arts teacher who trains the legendary Ulster hero Cú Chulainn in the arts of combat.
 Texts describe her homeland as Scotland ("Alpeach"); she is especially associated with the Isle of Skye, where her residence "Dún Scáith", or "Dun Sgathaich" (Fortress of Shadows), stands.
 She is called "the Shadow" and "Warrior Maid" and is the rival and sister of Aífe, both daughters of Árd-Greimne of Lethra.
Fleance (or Fléance) is a figure in legendary Scottish history.
 He was depicted by 16th-century historians as the son of Lord Banquo, Thane of Lochaber, and the ancestor of the kings of the House of Stuart.
 Fleance is best known as a character in William Shakespeare's play "Macbeth", in which the Three Witches prophesy that Banquo's descendants shall be kings.
 Some screen adaptations of the story expand on Fleance's role by showing his return to the kingdom after Macbeth's death.
The Innes Review is a biannual academic journal, published by Edinburgh University Press on behalf of the Scottish Catholic Historical Association in May and November of each year.
 It was founded in 1950 and covers the part played by the Catholic Church in Scottish history.
 It includes all aspects of Scottish history and culture, especially ones related to religious history.
Arson in medieval Scandinavia (Old Norse "hús-brenna "or "hús-bruni, ""house-burning") was a technique sometimes employed in blood feuds and political conflicts in order to assassinate someone.
 In committing arson, a group of attackers would set fire to the home of an opponent, sometimes by quickly and surreptitiously piling wood, brush and other combustible materials against the exterior of a dwelling and set it on fire.
 Typically the attackers would surround the house to prevent the escape of its inhabitants, although women, the elderly, and small children were sometimes allowed to leave.
The Third Murderer is a character in William Shakespeare's tragedy "Macbeth" (1606).
 He appears in one scene (3.3), joining the First and Second Murderers to assassinate Banquo and Fleance, at the orders of Macbeth.
The Highland Potato Famine (Scottish Gaelic: "Gaiseadh a' bhuntàta" ) was a period of 19th century Highland and Scottish history (1846 to roughly 1856) over which the agricultural communities of the Hebrides and the western Gàidhealtachd (Scottish Highlands) saw their potato crop (upon which they had become over-reliant) repeatedly devastated by potato blight.
 It was part of the wider food crisis facing Northern Europe caused by potato blight during the mid-1840s, whose most famous manifestation is the Great Irish Famine, but compared to its Irish counterpart it was much less extensive (the population at risk was never more than 200,000) and took many fewer lives (prompt and major charitable efforts by the rest of the United Kingdom ensured that there was relatively little starvation).
 The terms on which charitable relief was given, however, led to destitution and malnutrition amongst its recipients.
 A government enquiry could suggest no short-term solution other than reduction of the population of the area at risk by emigration to Canada or Australia.
 Highland landlords organised the emigration of about 16,000 of their tenants (chiefly to Canada); many Gaels made their own way to other destinations in the Scottish Lowlands or further afield and it is estimated that about a third of the population of the western Scottish Highlands (about 90,000) emigrated between 1841 and 1861.
Edward J. Cowan FRSE is a Scottish historian.
 He is Director of the University of Glasgow's Dumfries Campus and Professor of Scottish History and Literature.
 His main research interests are with the history of Viking Scotland, the Scottish Wars of Independence, Early Modern Scottish Political Thought, the Covenanters, Scottish Emigration history and the Scots in the Arctic and Pacific North West.
Lynch was born in Aberdeen.
 He was educated at Aberdeen Grammar School before taking degrees at the University of Aberdeen and the University of London.
 His first academic post was a lectureship in the history department at University College, Bangor (now Bangor University) from 1971-1979.
 From there he took up a lectureship in the Scottish history department at the University of Edinburgh, where, in 1993, he was appointed Sir William Fraser Professor of Scottish History and Palaeography, holding this Chair—the oldest and most distinguished Scottish history professorship in the world—until his retirement in 2005.
 As Professor he served as chairman of the Ancient Monuments Board for Scotland (1996-2002), president of the Society of Antiquaries of Scotland (1996-1999), and a trustee of the National Museum of Scotland (2002-2005).