If you haven't seen Netflix's Crime Scene: The Vanishing at the Cecil Hotel documentary series, you may not be familiar with the case of Elisa Lam and her mysterious death.

The documentary follows the unbelievable story of Elisa Lam and her disappearance while she was staying at the infamous Cecil Hotel in Los Angeles.

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CCTV footage shows eerie clips of Canadian student Elisa Lam as she shows erratic behaviour as she uses the elevator in the hotel before her body was eventually discovered in one of the building's water tanks - but it remains a mystery as to how she ended up there.

The footage was originally released to the public back in 2013 and showed Elisa's behaviour only hours before she vanished.

True crime fans now have a new theory that Elisa was playing a terrifying ritual called The Elevator Game as it could explain her erratic and unusual behaviour.

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The game sees the player visit different floors in a lift as a way to get into a "new dimension."

The rules are that the player must get in alone but things then change as someone else joins.

The player must get on at the first floor before travelling to the second, then to the sixth and back to the second. They then go up to the 10 before going down to the fifth and it is important they don't get out at any point.

The game then supposedly sees a mysterious woman enter the lift on the fifth floor but the player cannot interact with her. The player then must push the button to the first floor again.

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If the lift then goes down, the player needs to leave the building without looking back but if it goes to the 10th floor, the player will enter a new dimension.

In the CCTV footage seen before Elisa's death, she is seen pressing different numbers on the lift as she entered which has left many to believe she was playing this game.

Elisa's death was ruled as an accidental drowning and her bipolar disorder diagnosis has been determined as a significant factor in her cause of death.