Lancelot falls in love with Guinevere, who is due to be married to King Arthur. Meanwhile, a violent warlord tries to seize power from Arthur and his Knights of the Round Table.
 
If you like Robin Hood: Prince of Thieves (1991), then you'll like this one too.
 
FUN FACT:  Unlike many of the previous Arthurian films that drew to greater or lesser extent from Sir Thomas Malory's (1415-1471) "Le Morte d'Arthur," this film clearly drew from the romances written by French poet Chrétien de Troyes (1130-1191), who actually invented the character of Lancelot.