For several decades, the human race has slowly, but steady been colonizing the Solar system, expanding outwards from their planet of origin, know as Ghara. This process has been far from painless, having been marked by strife and unrest, especially between the Federation lead by Ghara and New Jordan, the only planet that has so far been successful in declaring its independence from the Federation, and has even been able to set itself up as as the only other superpower in the solar system to serious challenge the Federation. Recently the discovery of tyllanium, a rare mineral that has proved crucial in the development new innovative technology, has lead to increased competition between the Federation and New Jordan, as they struggle to outmanoeuvre each other in taking control of the few tyllanium deposits. Matters have not been made less complicated by the fact that Drovia, a colony controlled by the Federation, and the home of the largest known quantity of tyllanium, has started to agitate for its independence, demanding the right to determine its own fate on the solar stage. Ghara not being ready to grant Drovia independence and thereby letting go of its precious tyllanium, have caused tensions to inflame. With neither side willing to budge, and with rumors about a possible Drovian revolt in the near future and that New Jordan is poised to come to their aid if it were to happen, many fear that an interplanetary war is forthcoming.
Chaught in the middle of all this is agent Neil Conrad of the Central Department of Investigation (CDI), the main federal authority in charge of investigating major crimes on Ghara. When Joesph Banny, Drovia's foreign minister, is suddenly assassinated mere hours before he was supposed to meet with the Federation's president to discuss a diplomatic solution to their disagreements, Conrad and his partner, Gary Long, is put in charge of the investigation, and must race against the clock to solve the crime before tensions boil over; something which could easily start a devastating war. Along the way, Conrad uncovers a conspiracy that forces him to come up close of the darker and more rotten parts of the Federation, and seriously challenges his convictions.
- And Now for Someone Completely Different: The prologue sequence puts the player in the shoes of the teenage girl Mira as she experiences the infamous "Sector II incident" on Drovia. After this, the story jumps 40 years ahead in time and introduces us to Neil.
- Cigarette of Anxiety: Most of the time, it is up to the player whether Neil smokes a cigarette or not. Neil will, however, on a couple of occasions where he is under especially hard moral stress light up a smoke unprompted by the player.
- Cyberpunk: Present to some degree. It is a noir story set in a sci-fi future after all. Much attention is drawn to how the society of Ghara and the Federation at large is chafing under the corrosive power of the capital the various Mega-Corp are utilizing in an attempt to consolidate their power over the federal government, leading to a ever-worsening income inequality gap, which is further resulting in increasing social unrest as more and more people are finding it harder to make ends meet.
- The Federation: The Federation certainly likes to portray itself that way. Both Neil and many other character notices that in effect it is not always that way, as various Mega Corps are heavily involved with the government, meaning that it often favors them above everything else.
- Golden Ending: While most of the Multiple Endings are Bittersweet to some degree or another, some of the variations that have personal meaning to Neil are unquestionably happy. If he manages to rescue his daugther, Laura, from the mercenary company, reconnect with his ex-wife, Cat, and make Zora reconsider her life-choices, making her pull a HeelFace Turn at the end, Neil is ultimately at peace and happy with what he has achieved, no matter what else has happened.
- I Have Your Wife: The mercenary company involved in the conspiracy abduct Neil's daugther, Laura, to blackmail him into aiding them.
- Last-Second Ending Choice: Downplayed. The most important choice that Neil faces comes right at the end, where he either chooses to leak the truth about the conspiracy surrounding the Sector II Incident or keep it a secret for now. The choice has so far reaching consequences that it effectively determines the tone for the entire Modular Epilogue, but some of Neil's earlier choices come into play when determining the rest of it.
- Planet Terra: A twist on the trope, since the story of Lacuna takes place in a solar system that is evidently different from the real life one. But the Earth analogue is called "Ghara".
- Smoking Is Not Cool: Downplayed. A more technologically advanced society have lead to smoking becoming gradually less of a health risk, but it is still something that is considered an addiction. Neil is actively trying to quit smoking, and the game both rewards and punishes you for to indulging and refusing to indulge him.
- To Be Lawful or Good: Many of the moral choices Conrad faces boil down to this. Often times, the question he faces is whether to follow procedure as a CDI agent and uphold the law according to its letter, or show leniency and try to put justice before the law.
- Unobtainium: Tyllanium is a rare mineral that is hard to acquire, yet it forms the basis of a lot of modern technology, especially it allows for production of batteries that are several times more effective than lithium-base ones. Hence why controlling it has become an important political question.