In "The Hidden", players choose the role of either a near invisible killer, Subject 617, or one member of an Intercept squad who have to capture him, I.R.I.S. In the simple but challenging gameplay of an 'one against all'? mode, Subject 617 creeps/sneaks through the maps armed only with a knife and three pipe bombs. The IRIS team carry a selection of weaponry, fully customisable at round start, from F2000 assault rifles through to shotguns or sub machine guns as well as a pistol as a secondary weapon.

However, they can hardly see Subject 617 as, just like the 'Predator', only the outline of his silhouette is visible. On top of that the Hidden also moves a little faster and has many abilites such as pouncing, wall grabbing, corpse pinning and the fatal pigsticker attack. Therefore co-operation is necessary for I.R.I.S. if they wish to prevail (if they dont want to become the prey/victim themselves).

This leads to an outstanding gaming experience on public servers: The I.R.I.S team creep/sneak through the corridors, back to back & covering each other whilst Subject 617 lurks in dark corners choosing his time to attack. The player who finally kills the Hidden takes over the role & from then on he can roam like a ghost through the corridors.


In the early 1950's human genetics experimentation was taking its first, tentative, steps. Amongst many other black projects, a team of British scientists working at a Infinitum Research experimental station stumbled across some remarkable phenomenon involving DNA manipulation. This led to deeper research with dangerously unpredictable results, often leading to human patients losing their lives in irresponsible and immoral experiments.

Time passed on, and by the mid 1990's the failure rate of the experiments had been reduced from 75% to a mere 15%, enough for Infinitum to move onto the next stage, Biological Light Refraction. The British team were hoping to unravel the possibilities of light manipulation to create the perfect covert military agent. Early into the new millennium, due to a gross miscalculation, a series of tests on Subject 617 led to a massive synaptic trauma leaving the patient with multiple genetic anomalies.

The subject was left in constant pain and with unstable DNA. The subject escaped captivity, killing anyone that got in its way, the I.R.I.S (Infinitum Research Intercept Squad) team have been deployed to return the subject to a maximum security Infinitum Research facility for further study and dissection. The entire project was considered a failure, all funding ceased and development was discontinued. All records and traces of the experiments were destroyed. Infinitum Research denies all knowledge of any form of human DNA manipulation but are more than happy to comment on the possibilities of cloning human organs inside suitable animal donors. It is believed that these organ cloning experiments form the main cover for their human genetic manipulation experimentation.

As the I.R.I.S team close their net around it, subject 617, known as The Hidden must turn the tables becoming the hunter instead of the hunted!

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2 comments by Boxy on Sep 8th, 2007

While it's not Beta 5, we felt that enough's enough and that we had to get something out the door. So while this update does nothing on the code side of things (we didn't want to go back and try and jury-rig the old code base into a releaseable state - the additional problems that would create would be endless!) it does update the mods steamappid to 215 (we appreciate that a number of players and servers have already done this, but with this update everyone should be on the same playing field and we should have no more problems with one group being unable to play on certain servers!)

We've scrapped Manor (if you've been following the forum, you'll be aware of this) but rather than leave you with one less map, we've fixed up hdn_origin by removing the lag inducing shakes and replaced manor with the much more atmospheric and decidely sexy Decay.

Aside from those major changes, this update includes a number of alterations to materials and models and includes a whole new look and feel to the menus and front end! Though keep in mind, we have held back some art updates for Beta 5, just so we've got some new shinies to go along with the new gameplay mode and feature set.

NOTE: This update breaks compatibility between 4A clients and 4B servers (and vice versa) due to material alterations.

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Hidden : Source Beta 4b Server

Hidden : Source Beta 4b Server

Sep 8, 2007 Full Version 48 comments

This is the complete installer for Hidden Source beta 4b dedicated servers - if you are already running a beta 4a server, you may wish to only download...

Hidden Source Beta 4b Server update

Hidden Source Beta 4b Server update

Sep 8, 2007 Patch 3 comments

This is the update file for existing beta 4b dedicated servers, it does include new binary files as they remained unchanged. Please note, you should remove...

Hidden Source beta 4b Client Update

Hidden Source beta 4b Client Update

Sep 8, 2007 Patch 66 comments

This is the client update for the Beta 4b release of Hidden Source, please only use this if you have an existing Beta 4a install you wish to update ...

Hidden Source Beta 4b

Hidden Source Beta 4b

Sep 8, 2007 Full Version 501 comments

This is a full installer for Beta 4b of Hidden Source - it introduces a new map, hdn_decay and a number of graphical alterations. If you do not have an...

Hidden : Source Beta 4a Client Update

Hidden : Source Beta 4a Client Update

Jun 14, 2006 Patch 4 comments

This is a Client only update to the recently released Beta 4 of , it fixes a number of small issues and make some gameplay tweaks for balancing. For more...

Hidden : Source Beta 4a Server Update

Hidden : Source Beta 4a Server Update

Jun 14, 2006 Patch 1 comment

This is a Server only update to the recently released Beta 4 of , it fixes a number of small issues and make some gameplay tweaks for balancing. For more...

Post comment Comments  (30 - 40 of 538)
TheOneMuffin May 31 2013, 11:10pm says:

This DOES require HL2 because it wasn't made with the Orange Box Engine.

-3 votes     reply to comment
Guest Sep 18 2013, 2:57pm replied:

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Guest Jun 15 2013, 3:59am buried:

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Willow. Jul 19 2013, 2:34am replied:

That's not nice.

+1 vote     reply to comment
josephphirmis Jul 28 2013, 11:13am replied:

lol nice profile pic :P

+3 votes     reply to comment
Dragonxxx Apr 24 2013, 5:58pm says:

I got a quick questions. To download this do you need HL 2 or is it any source game like CS or HL episode 1 or 2? I have it but Im trying to find out what you need, also because my friends want to start playing, is this just for the sdk tool? can it work if you have access to the SDK 2006 - 2007 or do you needed to have HL..

+1 vote     reply to comment
Guest Aug 18 2013, 4:26pm replied:

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Jonathan156 Apr 25 2013, 11:39pm replied:

it can work with sdk 2007
it works with no more room in hell and resistance and liberation(both of them are hl2 mod)

+3 votes     reply to comment
deathreaper56 Apr 1 2013, 6:02am says:

how do you download the hidden every time i try it says its download i search through every think and its not there

0 votes     reply to comment
RU55IO Mar 21 2013, 7:44pm says:

I want to say that after installing everything needed, the game won't launch on Steam. I click the "play" button and nothing seems to happen.

+2 votes     reply to comment
ALPHA-1 Jul 1 2013, 1:50am replied:

install source SDK base 2007

+1 vote     reply to comment
Guest Apr 13 2013, 2:36pm replied:

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Guest Mar 27 2013, 8:49pm replied:

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ray12370 Mar 16 2013, 11:24am says:


+3 votes     reply to comment
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Release Date
Released Oct 1, 2007
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670 votes submitted.

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Highest Rated (2 agree) 10/10

One the most fun Source mods out there, even in just a beta form.

Easily deserving a 10/10.

Tip for IRIS players: Hunt the Hidden, don't let him hunt you.

Fun thing for Hidden players: Get really good at playing as the Hidden, then play against about 3 noob IRIS players, and scare the hell outta them. :D

Jan 30 2011, 2:00pm by MattmanDude

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