Song of the Deep is Insomniac’s New Game Inspired by Irish Myth

Insomniac Games has announced Song of the Deep, a 2D side-scrolling adventure inspired by Irish myths and modeled after games such as Castlevania: Symphony of the Night and Metroid. 

Song of the Deep will be available digitally this spring for PC, PlayStation 4, and Xbox One, with a physical edition available exclusively through GameStop, which is the title's publisher (you read that correctly). GameStop will help promote the game and a line of associated merchandise but is not involved in the creative process. 

Taking on the role of a girl called Merryn, players will set off from her home in County Clare on Ireland's Atlantic coast and build a ramshackle submarine to find her missing fisherman father. Merryn will face off against mythical sea creatures in combat and be challenged by a range of puzzles, while unlocking new upgrades will allow her to explore additional areas of the game world.

You will be able to exit the submarine but presumably only for a limited period of time. GameSpot has an interview with GameStop and Insomniac staff involved in the project if you want to know more.