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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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.

Personally, I think I have too much bloom. Maybe that's the trouble with me

Personally, I think I have too much bloom. Maybe that's the trouble with me

9 years ago News 1 comment

Ahha, a progress report! While I do not exactly bring the best of news, in that this is not going to give you a date for our next release, it should at...

Hidden Stats Launched

Hidden Stats Launched

9 years ago News 2 comments

Dear ModDB, My name is Robert "RaideR" Baxter-Kaneen, team leader of The team and I have been working on this service for about 4 weeks, and...

Hidden Source Beta 4 Released!

Hidden Source Beta 4 Released!

9 years ago News 7 comments

We said we were going to attempt monthly updates from here to the end, and we have 'near enough' done it this time, give or take a week. In our mad rush...

Hidden Source updates to Beta 4!

Hidden Source updates to Beta 4!

9 years ago News 0 comments

Falling just over the 4 week deadline we set ourselves at the release of Beta 3, it's here, the smaller but no less tasty, Beta 4! As you may appreciate...

RSS feed Downloads
Hidden : Source Beta 4b Server

Hidden : Source Beta 4b Server

8 years ago 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

8 years ago 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

8 years ago Patch 67 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

8 years ago Full Version 516 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

9 years ago 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

9 years ago 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  (60 - 70 of 545)
TheOneMuffin Oct 5 2012 says:

Guys, the creator is reviving the mod, go to the website and check it out! Hope to see the game get even better now.

+8 votes     reply to comment
Guest Jan 14 2013 replied:

This comment is currently awaiting admin approval, join now to view.

Dieger Nov 10 2012 replied:

im guessing we have seananners to thank :D

+2 votes     reply to comment
Guest Jan 9 2013 replied:

hey do u know how i can get into a server on the hidden, i cant find any!

+1 vote     reply to comment
FSugar Oct 18 2012 replied:

how can it be any better? the mod is awesome, I really have no idea what can he add more

+2 votes     reply to comment
0rpheus Nov 9 2012 replied:

There's always room for improvement, no matter how good a mod/game is

+3 votes     reply to comment
Dejected-Angel Sep 28 2012 buried:


Why does the description reminds me of Natural Selection?

-7 votes     reply to comment
Mustard Sep 18 2012 says:

I'm so glad this mod is gaining players again, but i keep getting an NSIS error on the installer? Anyone know a fix? I've tried a few but no luck..

+1 vote     reply to comment
MiniDude Sep 16 2012 says:

SeaNanners made this game alive again xD, i loved it back before this and still love it now, new maps would be nice though.

I also made a PlayDB video if you wanna check it, not as good as SeaNanners but heyyyyy :D

+1 vote     reply to comment
adam_825 Sep 30 2012 replied:

I got here from Criken2

+1 vote     reply to comment
DeathPants Sep 8 2012 says:

I keep getting Connection Problems on my side. Why is that?...

+1 vote     reply to comment
KapitoIIIka Sep 1 2012 says:

can someone post it on Steam Greenlight?

+5 votes     reply to comment
TailGunnner Feb 1 2013 replied:

1. On steam Grean ligth Only the depovers of the games has awaibility to post thair games.

+1 vote     reply to comment
SirWallyWombat Nov 24 2012 replied:

This game/mod has had a steam page for years.

+1 vote     reply to comment
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Half-Life 2
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Released 2007
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671 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 by MattmanDude

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Hidden Source
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1 year ago
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