#BBCtrending: The story behind #Neknomination
5 February 2014 Last updated at 13:17 GMT
The online drinking game 'Neknomination', which involves filming oneself whilst 'necking' a drink, has gone viral on Facebook.
Participants post their videos on social media and then nominate someone else to do the same.
Its popularity has come at a price, after a teenager died in the Republic of Ireland who allegedly took part in a 'Neknomination'.
Produced by Anne-Marie Tomchak and Neil Meads.
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