Arthur fulfills his fate by bringing together the Knights of the Round Table at Camelot and unifying the country. However, this flawed monarch faces greater tests ahead in pursuit of love, the Holy Grail, and his nation's survival.
| Actor | Role |
|---|---|
 Nigel TerryKing Arthur | King Arthur |
 Nicol WilliamsonMerlin | Merlin |
 Helen MirrenMorgana | Morgana |
 Nicholas ClayLancelot | Lancelot |
 Paul GeoffreyPerceval | Perceval |
 Cherie LunghiGuenevere | Guenevere |
 Robert AddieMordred | Mordred |
 Gabriel ByrneUther | Uther |
 Keith BuckleyUryens | Uryens |
 Katrine BoormanIgrayne | Igrayne |
 Corin RedgraveCornwall | Cornwall |
 Liam NeesonGawain | Gawain |
| NNiall O'BrienKay | Kay |
 Patrick StewartLeondegrance | Leondegrance |
 Clive SwiftEctor | Ector |
 Ciarán HindsLot | Lot |
| LLiam O'CallaghanSadok | Sadok |
| MMichael MuldoonAstamor | Astamor |
 Charley BoormanBoy Mordred | Boy Mordred |
 Brid BrennanLady in Waiting | Lady in Waiting |
| GGarrett KeoghMador | Mador |
| EEmmet BerginUlfius | Ulfius |
| EEamon KellyAbbot | Abbot |
| GGerard Mannix FlynnMordred's Lieutenant | Mordred's Lieutenant |
| BBarbara ByrneYoung Morgana | Young Morgana |
| KKay MaclarenAged Morgana | Aged Morgana |
 Joelle HélaryLady of the Lake | Lady of the Lake |
 Conor LambertPuppeteer | Puppeteer |
 Prudence Wright HolmesSunshine | Sunshine |
| PPaul MarkeyPeasant Boy | Peasant Boy |