Despite this freedom, the first half of the DLC on the ship favours stealth play. Indeed, one character positively enforces the approach, telling Jensen: "The longer you stay undetected, the brighter your future will be." Enemies hit hard and, if the alarm is raised, will quickly shunt you back into a tortuous loading screen. There are a few difficulty spikes early on in the episode that lead to frustration. With the lacklustre design of the ship - all identikit ladders and corridors leading up and down in an uninspiring spatial puzzle - motivation to progress is often low.
Play is linear and funnelled, with just the odd side quest to distract from the crosshair marker that leads you to the next plot trigger point. One early example asks you to fix a damaged stasis pod by replacing its electronic server. Not doing so will result in the death of whoever is hidden inside the pod, a rare moment to play saviour in an adventure that is almost all about playing killer. Irritatingly, side quests can be failed simply by leaving an area without having completed them, even though it's possible to freely return.
The structure of the episode takes cues from Metal Gear Solid 2, moving midway through from the storm-ridden ship to a hidden base that the ship docks at. This area, with its wider scope, is much more enjoyable, facilitating the sort of player freedom that marks out the main game. Here you'll even find a couple of allies who, in addition to providing weapons, offer some friendly human contact to inspire progress.
But the dark, repetitive environments fail to inspire in the same way. On reflection, for all Human Revolution's interesting mechanics and immersive elements, the world which you are asked to pit your skills against can fail to match up to the tools in your hands. The range of ways to interact with environments is wide and deep, but the applications can sometimes feel a little limited, and this is never more evident than in The Missing Link.
Close to the end of the episode, Eidos Montreal's developers attempts to exorcise the spectre of Human Revolution's sub-par boss battles with a creation of its own. As this enemy can be taken down in creative ways by players who have not augmented the 'combat' aspect of their character, they go someway to succeeding.
But, elsewhere, The Missing Link feels routine, uninspired. There's no grand hook to the episode, leaving one with the feeling that it's here to plug a narrative gap in the main game rather than justify its presence on its own merits. The opportunity to revisit Human Revolution is a welcome one, but this is a competent expansion rather than an unmissable one.
6 / 10