A Lewisham student has created a unique challenge for puzzle fans - the world's smallest 'escape room', the size of a treasure chest.

Its designer says the game - called 'The Subject' - is "intended to induce claustrophobia, desperation and dread" because it's set in a box about the same size as a trunk or small coffin.

Based on horrifying stories of Cold War CIA mind control programmes, the two player game sees one person locked inside the box with just a pencil, paper, torch, and a series of cryptic messages and clues written across the walls - playing the role of an experiment subject.

The second player, acting as a special agent, has to help them escape.

Outside the box is a coded lockbox and another series of documents. Players have to work together to solve the puzzles and unlock the box.

The escape room phenomenon started in Japan but has seen a worldwide boom in recent years.

The Subject forms part of Experiments in Play, the Goldsmiths MA Independent Games and Playable Experience Design Degree Show starting today (Thurs) and ending Saturday.

Student George Larkwright, 24, created the experience in response to the trend for escape rooms at corporate events, where players finish the game "giggling and merry and ready for a selfie."

The idea first came to him after he watched a scene in Tarantino's Kill Bill 2 in which The Bride is trapped in a wooden coffin.

He said: "Escape Rooms are increasingly popular, they've become a middle-class millennial party experience or corporate team building gimmick.

"They're an experience driven by social media for social media: the goal is now to get a 'we escaped' selfie at the end.

"I want to strip users of their phones and lock them in a box with only a torch and their own ingenuity.

"I don't want people to finish the game and be giggling and merry and ready for a selfie.

"I want participants to emerge haggard, almost aged by the experience, but also triumphant, proud of navigating a game that is both physically and mentally taxing."

Using his extensive theatre writing experience, George wanted to write a discoverable story rather than a spoon-fed narrative.

During the experience, Player Two can learn more about The Subject, where they came from, and what the purposes of the experiments conducted on them are.

Player One's story is focused on delving into the psyche of The Subject during their ordeal.

Measuring just 120cm x 70cm x 50cm, the new game beats the previous smallest escape room, which is 250cm long, 150cm wide and 283cm high.

After its showing at the Experiments in Play show, Larkwright plans to rebuild the box with a greater focus on portability, before taking the project on tour next summer.and their shareholders."