In the blue vault of the sky, in the castle of the God of Thunder, the Baltic gods gather to give audience to the Father of Fate. Here, in the place where eternal light resides, he tells them the story of Christ. He tells them that Christ’s teachings have been accepted by nations of the world. But, the Father of Fate explains, people perverted those teachings to their own evil ends. And now these very people have decreed that the Christian faith will be brought to the lands of the Baltic.
The God of Thunder speaks up, warning that those who have taken it upon themselves to carry the religion of Christ forth intend to occupy the Baltic region and make slaves of its people. He vows that he will do what he can to help the peoples of the Baltic defend themselves against these foreigners and their evil designs.
The gods and goddesses huddle amongst themselves and discuss how they can give assistance to the Baltic mortals. Staburadze, who lives in a crystal palace in the depths of the mighty Daugava River, comes forward to tell the other deities of her encounter with a youth whom she saved from death. She would like to keep him with her beneath the river lest he return to the surface and turn into stone. The God of Thunder, however, proclaims that the youth has been blessed and that he is destined for glory.
Some time later, the youth leaves the waters beneath the river. The chieftain Lielvarde adopts the youth as his own son. One day a vicious bear attacks the chieftain. The youth intervenes and wrestles the bear to the ground.
Grabbing the beast by the jaws, he rips the bear apart with nothing but his hands. The old chieftain is amazed by the boy’s strength and courage, and so he decides to reveal what has been said by the gods about the destiny of the impressive young man: he is to become a hero of his people. Henceforth, the youth is known as Lacplesis, the Bear Slayer. The chieftain provides him with a fine horse, a sword, shield, silver spurs and a marten-fur hat. The Bear Slayer then rides off to gain wisdom in the ancient Burtnieku school of wisdom.
On his way to Burtnieku, the Bear Slayer asks for lodgings at the castle of Aizkraukle, which stands in a desolate spot, far from the shores of the Daugava River. It is a place of notorious gloom. Here the Bear Slayer encounters Spidala, the gorgeous but evil daughter of the chieftain of Aizkraukle. The Bear Slayer, in young manhood, is enraptured by the sultry, dark-eyed Spidala. But to his horror, he discovers that she has made a pact with the devil.
One night, the Bear Slayer secretly follows Spidala into the Devil’s Pit. He draws close to a large house. Inside, he witnesses evil that is ghastlier than he can imagine. He sees the decadent Spidala and other young witches undress and then cavort with wicked demons. They partake in a bloody feast of children’s hands and squirming eels. The feast is then disrupted by the old Devil, Crooked Cap himself. He explodes into the chamber on a golden carriage that is pulled by a fire-breathing dragon.
The demonic bunch then encircle a trembling mortal: it is Kangars, deemed by his people to be a holy man. But, as the Bear Slayer quickly discovers, Kangars is the most despicable and lowly of traitors. Kangars is spared from being chewed up by the Devil’s dragon by promising to disavow his god and to betray his people, condemning them to slavery at the hands of the foreigners now heading across the Baltic Sea.
The Bear Slayer has had enough of this hideous scene. He slips out of the house to make his way back to Aizkraukle castle. But an old witch sees the Bear Slayer and tells Spidala to dispose of him. She pursues him on a river, where the Bear Slayer’s log is sucked down into the whirlpool of Staburags—to what should be a certain death. But the gods spare him. The Bear Slayer wakes up unscathed in the crystal chambers of Staburadze, where he encounters the beautiful Laimdota, the daughter of the wise old chieftain, Burtnieks. She has brains to match her physical charms! It is love at first sight. Eventually, the Bear Slayer must take leave of the beautiful Laimdota. Back on the river, the Bear Slayer meets Koknesis-another youth of legendary strength—and they become friends. Together, they journey back to the Aizkraukle castle, where the evil Spidala is shocked to find that the Bear Slayer is still alive.
After some time, the two friends, the Bear Slayer and Koknesis, depart for Burtnieku castle to learn the wisdom of the ancients.
From : http://www.balticsworldwide.com/news/features/bear_slayer.htm