The giant Red Cup installation - that smells like a gingerbread latte - will be at Kings Cross station from Tuesday 3 November until Friday (6 November) and will gradually light up as consumers tweet #RedCups.
Tweets with the hashtag will feature across digital display boards throughout Kings Cross and Starbucks will also dish out gift cards.
The campaign introduces its seasonal drinks range (which come in red cups) including Gingerbread Latte, Toffee Nut Latte, Eggnog Latte and Honey and Almond Hot Chocolate.
The brand, in partnership with Twitter, has also created a Red Cup hash-flag which appears whenever #RedCups is tweeted.
"We wanted to declare the red cups season officially open with an inclusive campaign showcasing the great organic community #RedCups creates online," said Steve Flanagan, UK marketing director.
Agency: Manning Gottlieb OMD