The player controls a young woman named Kay who suffers from such strong loneliness that her inner feelings of hopelessness, anger and worthlessness turn to the outside and she becomes a monster.

As Kay, the player explores a seemingly empty flooded city and interacts with its scaly red-eyed creatures to reveal why she turned into a monster.

[2] As the game progresses, it's revealed that Kay's parents Adam and Vivienne had her at a very young age, followed by a brother named Sonny 12 years later.

Kay learns a lot about herself by understanding the value of listening, coming to term with her flaws, and not just empathizing with family but also accepting that a simple fix isn't always possible.

IGN summarised that "Sea of Solitude gives you a beautiful world and an intriguing story but the gameplay fails to evolve enough to make this a compelling adventure".

[18] Game Revolution wrote "In essence, it’s a boat that looks nice from the outside until you jump inside and notice all the holes actively trying to sink the whole thing.