Back in 2005-2007, when Valve still had episodic system in mind the development of one of Half-Life 2 episodes was given to outsource company. At first it was Warren Spector's Junction Point Studios, and then since 2006 - Arkane. Before this day we only had some pieces of informations, few screenshots and model renders from Arkane's project. For more information you could visit a discussion thread on our forums.
Today a new documentary about Arkane Studios was released on Noclip channel. As we predicted there was plenty of new information, screenshots, concept-art and video footages from the cancelled Half-Life 2 episode Return to Ravenholm.
Here's a short list with some of the facts from this video:
-A playable build still exists inside Arkane studio
-They had a build of Episode Four's previous iteration from JPS but from the looks of it they decided not to use their ideas.
-Inside their team this project was called just "Ravenholm"
-The protagonist was Lt. Shephard from Opposing Force (it seems G-Man gave him a nice promotion, from corporal all the way ti leutenant )
-The main part of the game was to be insite an abandoned asylum, most likely somewhere not far from Ravenholm, and near the end of it in the town itself.
-Father Grigori was making some experiments with Headcrab's toxins in hopes to find immunization from them and we were to assist him in this
-Grigori was testing the cure's prototypes on animals and on himself. Later in the game he would get mutations that he would try to hide, e.g. under the hood.
-In the end of the game he would become fully mutated and most likely would be some kind of final boss.
-They planned to use Viktor Antonov's idea cut from HL2 - huge wind turbines that were built to generate electricity
-Two of the new enemies were mutated monkeys that are scared of flashlight and zombies that could spit acid
-Some of the new wepons were nailgun, some kind of plazma weapon and leaf blower
-Nailgun could be used to solve puzzles with electricity by connecting the circuits with bolts с
-Leaf blower could be used for rocket jumps
-The ending wasn't revealed because according to the developers Valve still can somehow use it in their next games
Of course it's better to see all this byyourself and enjy another portion of content that unfortunately most likely will never be released as a full game.