The Adventure Synopsis explains what happens, it all starts with a distress call from an abandoned planet called Zeta Gruis VII, where the away team will find a deserted alien city - or is it? Meanwhile the ship in orbit is harassed by another vessel. Intended for The Next Generation era, quite precisely dated to the second season, but there's scope for variation although earlier could be a bit tricky with races and artefacts as yet unencountered in the show.
Part of the adventure focuses on characters reliving past events - an opportunity to bring critical elements from each character's Lifepath up, or to explore unrecorded parts of their history, challenge values or look at inter-character relationships. Then there is an investigation to discover why here and now? Plenty to keep the party on their toes.
The first Act covers exploration of the alien city and attacks by alien wildlife... and then the hallucinations begin. The GM is advised to be sneaky about this, to introduce them slowly and to attempt to split the party up before unleasing the full force... and this moves smoothly into Act 2. It might be a bit tricky to run, as each character has their own memories replayed. It's suggested that separate scenes are run for each, although they're actually all happening at the same time. Hopefully at least some will manage to break free from the effect before the local wildlife catches up with them (although they too are affected!)... but that is when the enemy forces reveal themselves, in overwhelming numbers. The sun is rising too, which takes the temperature to unbearable levels. This is a set-up: it's intended for the characters to be captured to further the plot.
Act 3 provides the final stand-off between the party and their captors, mirrored by their ship overhead dealing with the vessel that is jamming their sensors. The party may try a spot of social engineering or break out by force, or - if their ship is successful in its conflict, a rescue party may arrive.
Overall this is a rather railroaded adventure, and one that some groups may find too psychological, too personal and introspective. Decide with care whether or not it will appeal to your players: with the right ones, though, it could prove memorable.