The founding character of the Channel Awesome site and the one that, in conjunction with the Five Second Movies, launched Doug Walker's career as an Internet celebrity.
The Nostalgia Critic is a cynical critic who, in his original run, reviewed movies and TV shows from The '80s, The '90s, and occasionally the early 2000s, although in a few cases he reviewed films from later years than this, such as his reviews of The Room (2003), Alone in the Dark (2005), and Ponyo (2008). He has a bit of a temper problem, but is otherwise very sarcastic.
After running for 222 episodes, Doug announced the Critic's retirement in September 2012 (reflected in the ending of To Boldly Flee and to a lesser extent, his Scooby-Doo review, which was the precursor to To Boldly Flee), so he could move on to other projects, the biggest being Demo Reel. He would continue to make cameos in other people's works and was still referenced in other people's works, but he did not intend to return except on special occasions...
...that was, until, on January 22, 2013, the Nostalgia Critic's return was announced, bringing the end of Demo Reel along with it. Episodes resumed February 5, 2013, with reviews on a fortnightly basis, though now with editorials and mini-reviews on the weeks in between, and no cutoff date.
The show also took on Malcolm Ray and Rachel Tietz, who played Tacoma Narrows and Rebecca Stoné on Demo Reel, respectively, as co-stars with skits done in between the reviews. In 2014, Tietz left the show to pursue an acting career in California, saying goodbye to the fans in the review of Face/Off, and was replaced with her friend Tamara Chambers, who had previously appeared in the review of Catwoman (2004). Tamara's own series, Tamara's Never Seen, where she reacts to popular movies she had never seen before, and Tamara Just Saw, where she reacts to movies still in theaters, has its own page.
In 2017, after several years where the mini-reviews were framed or categorized as editorials, fuller-sized but not fuller-produced reviews began appearing in the in-between weeks once again.
You can see his videos here. Recaps of his episodes are here. Vote on his best review here.