Forward. Former Sunderland youngster Cook flew out to Hungary to join the Hatters squad at their pre-season training camp, where he penned a two-year contract having turned down the offer of a new deal at Walsall.
The 26-year-old began his career in the Premier League, making his Black Cats debut as a substitute against Manchester United on Boxing Day 2010.
He gained experience on loan at Darlington, Walsall and Carlisle, before heading south to sign for Charlton Athletic in 2012.
Cook first worked with Town boss Nathan Jones at The Valley, and after spending two years at Walsall in League One, he jumped at the chance to be reunited with his old Addicks coach last summer.