Philip Seymour Hoffman at the UK premiere of The Ides of March #LFF

George Clooney at the UK premiere of The Ides of March #LFF

LFF #mysteryfilmstill No. 1 http://bit.ly/nuuXFf

is from Anonymous (2011)

LFF Mystery film stills are a nod to the BFI London Film Festival programme: http://bit.ly/pWXlPC

Can you identify LFF #mysteryfilmstill No. 1?

Mystery film stills are taken from the 55th BFI London Film Festival programme: http://bit.ly/pWXlPC

How would you like to sport an official London Film Festival t-shirt? Send us your festival reviews, using the #LFF hashtag, and we'll select five t-shirt winners at random.

Director Yorgos Lanthimos and Producer Athina Tsagari attend the UK premiere of Alps #LFF

Frederick Wiseman introduces his documentary Crazy Horse at the #LFF

Ralph Fiennes at the UK premiere of Coriolanus #LFF

Woody Harrelson at the UK premiere of Rampart. Catch his screen talk tomorrow: http://www.bfi.org.uk/lff/node/2051

Michael Fassbender at the UK premiere of Shame #LFF

Mike Leigh introduces his Screen Epiphany, The 400 Blows, at BFI Southbank, 11 October 2011.

Photo: @yvessalmon

Programmes for tonight's Opening Night screening of Fernando Meirelles' 360 #LFF

#mysteryfilmstill No. 28 http://twitpic.com/6v3puz

is from The New World (2005)

Mystery film stills are a nod to the BFI Southbank programme: http://bit.ly/c86sKu

Can you identify #mysteryfilmstill No. 28?

Mystery film stills are taken from the BFI Southbank Guide: http://bit.ly/c86sKu

#mysteryfilmstill No. 27 http://twitpic.com/6o72yh

is from Sweet Sixteen (2002)

Mystery film stills are a nod to the BFI Southbank programme: http://bit.ly/c86s

Can you identify #mysteryfilmstill No. 27?

Mystery film stills are taken from the BFI Southbank Guide: http://bit.ly/c86sKu

#mysteryfilmstill No. 26 http://twitpic.com/6o72yh

is from A Brighter Summer Day (1991)

Mystery film stills are a nod to the BFI Southbank programme: http://bit.ly/c86sKu

Can you identify #mysteryfilmstill No. 26?

Mystery film stills are taken from the BFI Southbank Guide: http://bit.ly/c86sKu

#mysteryfilmstill No. 25 http://twitpic.com/6kuxnb

is from Badlands (1974)

Mystery film stills are a nod to the BFI Southbank programme: http://bit.ly/c86sKu

Can you identify #mysteryfilmstill No. 25?

Mystery film stills are taken from the BFI Southbank Guide: http://bit.ly/c86sKu