Avsnitt 6

After happy years for Arn and his finally reunited family, king Knut is dying, spelling a bloody civil war. Fearing a Danish intervention would be fatal, the Folkungs arrange a deal by which Karl, whose father's throne Knut re-usurped, succeeds but must adopt Knut's firstborn Erik as crown prince. Rightly suspecting foul play, Arn sends his Danish former Templars squire along as supposed turncoat, in fact Eric's bodyguard . After he prevents Eric and his brothers, one of which is however slain, being cowardly drowned, Arn takes command of a revolt, heading for an epically bloody battle.