In the 2004 film King Arthur, Ioan Gruffudd portrays Lancelot.
The film stars Clive Owen as Arthur and presents its characters as Roman-era soldiers stationed in Britain. It is not a direct adaptation of one medieval Grail romance, but it incorporates Arthurian names, Christian imagery, and a mission involving a family protected near Hadrian’s Wall.
Gruffudd’s Lancelot is one of Arthur’s mounted companions and a member of the group of warriors serving Rome. The film gives the familiar legend a historically framed, action-adventure interpretation rather than the courtly structure of Malory or the French prose romances.
The movie is sometimes confused with First Knight, another modern Arthurian film, in which Lancelot is played by Richard Gere. That is a different production and does not feature Gruffudd.