After taking over from Lee Camp as Forest's number one midway through the 2012-13 season, Darlow established himself as one of the Sky Bet Championship's top goalkeepers with an impressive 2013-14 campaign.
He fought off pre-season competition from experienced Dutchman Dorus de Vries to retain his first-choice status and justified his position with a number of excellent performances, making 45 appearances, keeping 13 clean sheets and earning a move to Premier League side Newcastle United.
As part of the deal, Darlow returned to The City Ground on a season-long loan for the 2014-15 season and has kept his place between the sticks.
The keeper joined Forest's academy after leaving Aston Villa and made his first-team debut on the final day of the 2010-11 campaign, coming off the bench to replace Camp for the final 15 minutes of Forest's win at Crystal Palace.
He has previously had loan spells at Newport County and Walsall.