After rescuing Prince Justin from drowning, Marina falls in love with him. In a bid to be with Justin forever, Marian and her sea friends embark upon a quest to make her human and find themselves involved in many dangerous adventures.
Return to the Sea - When Queen Margaret and King Charles announce Justin's engagement to Cecily, Marina decides to return to the sea, to certain death, rather than live without him.
The Golden Table - After Hedwig and minions sink a ship, they find a Golden Tablet with an ancient magic formula for changing sea creatures into mortal form permanently.
Water, Water Everywhere - With the social event of the year - Costume Ball - approaching, Justin tells Queen Margaret and Cecily he is bringing a princess from a 'neighbouring kingdom' - Marina, in disguise.
A Leopard and Her Spots - When Barnabas' family goes visiting, Marina is left to babysit Barbanas, who has Mer-measles but insists on working on his new invention - Volcano Spinners - in his fabulous workshop.
Whither Though Goest - Hedwig pays Lothar, son of the king of Brackston, to arrange a phony peace conference to kidnap Justin, the designated delegate from Gandor.