Former Arsenal captain Thierry Henry has got fans guessing after posting picture of himself alongside singer-songwriter Robbie Williams on Twitter, cryptically promising 'something special' ahead of Red Nose Day 2015. The biennial television charity appeal, which is part of the wider Comic Relief campaign, is set to air this year on March 13. Williams, who has had UK No 1 singles with Millennium and Rock DJ, has taken part in previous Red Nose Day shows, and famously appeared dressed as a woman with Matt Lucas and David Walliams of the hit comedy series Little Britain in 2009. Thierry Henry poses with singer-songwriter Robbie Williams (left) ahead of Red Nose Day . The Frenchman is Arsenal's all-time leading goalscorer, netting 228 times for the north-London club . Williams (centre) appears with Little Britain's Matt Lucas (left) and David Walliams for Comic Relief in 2009 . It remains to be seen whether Henry, who retired from playing football last year, will be prepared to try something as daring. Since hanging up his boots, Arsenal's all-time leading goalscorer, has been working as a pundit for Sky Sports and taking the first steps into coaching, juggling a part-time role with the north London club's youth development teams. Henry is known to support a number of humanitarian causes and is an ambassador for the children's charity, UNICEF. Henry makes a point to fellow Sky Sports pundit Glenn Hoddle (right) ahead of the League Cup final . Williams performs at the Bambi Awards back in 2013 at the Stage Theatre in Berlin, Germany . Henry scores a penalty for Arsenal during the Premier League game against Charlton Athletic in 2007 .
Thierry Henry and Robbie Williams will work together for Red Nose Day . Former Arsenal captain Henry posted a picture of them on Twitter . Williams has appeared in Comic Relief sketches before . Red Nose Day will take place on March 13 .