Idun is the Norse goddess of spring, rejuvenation and eternal youth. She is the custodian of the golden apples of immortality which the gods must eat to preserve their youth.
In one Viking tale, Idun is tricked by Loki, god of mischief, and she and her apples are seized by the giant Thiassi and locked in his tower. The gods quickly begin to grow old, and they force Loki to rescue Idun. This he does by disguising himself as bird and flying into the tower where he changes Idun and her apples into a small nut that he grasps with his claws, and carries her back to the gods.
Idun is married to Bragi, god of poetry. Theirs is an idyllic union.