The space genre as a whole has suffered a rather large decline in popularity over the last few years and is gradually becoming a rare breed, much like flight-sims before it. And within the threadbare sci-fi milieu, true 3d space-based real-time strategy games are even rarer, with Homeworld 2 being the only game of note in the last few years. So it takes a brave developer to mark their entry into the industry with such a title, in what is now arguably a niche market. So up step Mithis Games and HD Interactive, with Nexus: The Jupiter Incident which, fortunately for them (and us), is rather good.

Nexus is the successor to Imperium Galactica I & II, having originally been planned as the third title in that series before changing moniker to Galaxy Andromeda. It was then dumped by publisher CDV, picked-up by Vivendi Universal and secured a final name change. For those familiar with any of the earlier titles, this shares little of the heritage or indeed mechanics of those games. Instead, Nexus is all about capital ship combat - big, hulking battleships blasting seven shades of shields out of each other, destroying everything else that gets in their way - so no resource gathering here. The idea then, is to simulate fleet-to-fleet combat and the manoeuvrings required by the captains of big ships, trying to hit big targets.

Of course, you need a reason to partake in this combat, and Nexus is happy to provide. During an unexpected skirmish with an unknown extraterrestrial race near Pluto, Captain Robert Cromwell is forced to seek refuge aboard an alien ship with the help of a friendly AI (yep, computer program), and head into a wormhole, being the only means of escape. Upon emerging in a new solar system inhabited by humans (which was settled years before by his feared-dead space-explorer father), Cromwell becomes allied with the humans and embroiled in a galactic war with a race known as the Gorgs. During the course of the campaign your mission is to fend-off the Gorgs whilst simultaneously trying to find out about the new alien menace (as encountered near Pluto) and to put a stop to their aspirations of universal domination.

Whilst it treads a fairly worn path of sci-fi conventions involving some tried-and-tested clichès, the story is well paced, and the presentation is polished, from the wonderful cut scenes to the mission briefings (which, in a nice touch, can be paused), right down to Cromwell's personal diary notes (which provide additional back-story). Still, as engaging as the plot is, it's really all about the combat, and it's here where the game attempts to leave its mark on the genre, because Nexus at times feels like the lovechild of a turn-based/RTS union, being more cerebral than the standard click-and-rush gameplay associated with the genre; think of it as a game of chess, rather than a by-the-numbers RTS title, on the prettiest-looking board you'll have seen in a long, long time to boot.

The first couple of missions serve as a tutorial, after which you can start to explore the tactical depth provided by the game. Mission objectives range from stealth to escort, defence to confrontation, and will give you between one and ten ships to command. Before any mission starts, though, you have the opportunity to outfit your fleet. This means that you pick all the equipment and fighter squadrons you require, taking account of the role you want the ship to fill. The amount of equipment allowed is governed by a simple resource point allocation granted to each ship, and with plenty of attachments available it's easy to spend a while building a diverse fleet. And diversity is the key; each ship has a hull, shields and devices (such as engines and weapons). Weapons will normally only be able to affect one of those areas, so it's unlikely that any one ship will be able to single-handedly destroy all in its path, so effective use of your units is paramount. You may decide, for example, to use a small, fast ship (or your fighter squadrons) to disable the enemies' shields, allowing the heavy guns to plough-in and pound the hull - combinations of units are your friend.

Once embroiled in the scrap, the slower pace of combat assists tactical play, and it's down to you to control ships using either stock commands (such as attack or guard), or take full control over every aspect, including what weapons to fire and when, and what speed to move at. This level of micro-management can be daunting but it does allow more precise control. The action can also be paused to let you take stock and think, which you'll need to do, as, in many of the missions you will face greater numbers. And, because no-one is equipped with a hackneyed Big Laser of Doom(TM) that destroys ships in a single blast, hitting devices to disable targets becomes a key strategy throughout the campaign. Once orders are given, each vessel will manoeuvre into position before unleashing a barrage of lasers, missiles and guns, whilst simultaneously attempting to dodge your aggressors' weapons. It's similar in essence to naval combat, with ships jockeying for position, trying to bring all weapons to bear whilst not exposing weaknesses.

One fight you needn't worry about, though, is with the interface, which is easy to use and presents all the information you need without clutter. Navigation around the 3d map is also a breeze, and in addition to the fully 3d camera it allows you to view the action from any angle and point on the map. And on occasion you'll probably want to view the action up close, as Nexus has a lush engine powering it. Each race's ships are distinct and well-modelled (if not a little stereotypical); get close to a human ship and you can read the designated name and number on the side, or watch the weapon turrets track and fire. Or maybe you fancy following a fighter as it makes a pass over an enemy ship, or maybe watch as a missile hits the target? Zoom the camera in when it does and the screen will shake violently. Whatever you fancy, the graphics are there to be admired, and at times it presents a vista akin to a big battle scene in any number of sci-fi films, with lasers projecting their searing light over the vast expanses of space.

That said, whilst your eyes feast on the graphical splendour, your ears will feel a little left out, as the aural experience is less enthralling. The classical score playing in the background is pleasant enough, but the weapons don't sound as impressive as you feel they could. The voice acting too, is a little hit-and-miss, with comic alien impersonations spoiling the good work of the human-speaking parts. There are some other niggles, too; the stealth missions are ill-conceived, being clumsy and frustrating, where success is more a result of luck rather than skill and judgement. There is also an RPG element that lets your crew level-up with experience, but it does feel a little tacked-on. Coupled with the fact that none of your characters can be killed, there is no emotional attachment to them; you can also be a little more gung-ho, safe in the knowledge that no matter what, they will always live to fight another day. Perhaps these are issues that could be addressed in an add-on pack or sequel, but to be fair none of these quibbles are major hang-ups though, and shouldn't detract from your enjoyment of the game or hamper your progress through the 26-mission campaign.

After you have completed the story mode, you can pit your tactical wits in three different game variants over the internet with up to eleven other people, or try your hand at making a mod for the game with the four included toolkits. Already the community is starting to talk about total conversions (with a request, incidentally, for a Freespace 2 mod already made), so there is enough to keep you occupied for a while.

To suggest that Nexus will have anywhere near the impact on the genre that Homeworld 2 achieved would be wide of the mark, but - all things considered - Nexus deserves success in its own right, because it is a well-rounded and polished product. Nexus is different enough to stand out from the (relatively small) crowd, and is a suitably dramatic space-opera RTS with a luscious graphical engine, 'just one more mission' appeal, and provides a challenge for new and seasoned players alike. If space strategy is your 'thing', and you don't mind the concept of micro-management of your ships, then you owe it to yourself to get this game.