Two mysterious individuals come to Babylon5, equipped with weird instruments, to learn the truth about Commander Sinclair's unexplained 24-hour blackout on the eve of the Minbari surrender that ended the war with Earth. This is indeed a major episode, one that sums up nicely the most important events in the pilot episode, and gives us precious insights into Sinclair's past, frame of mind and inner demons.
Toward the end of the Earth/Minbari war, as the Minbari fleet was about to reach Earth and end the war with a massive, genocidal attack, the remaining Earth forces were sent to meet the enemy fleet and borrow some time to let a few ships escape and insure the continuation of at least a fraction of the human race. In command of one the defending squadrons, Sinclair saw friends and comrades killed one by one until he decided to end his life pointing his Starfury on a collision course with a Minbari ship, in an attempt to go out in a blaze of glory and destruction.
The brutal, mind-twisting interrogation now slowly reveals that in the 24 hours he was supposedly unconscious, after blacking out in the maneuver, he was instead taken aboard the enemy ship and interrogated. That's when the Minbari learned something that compelled them to end the war then and there, and declare a surrender. The mysterious interrogators are convinced that they wanted to use Sinclair (and maybe others like him) as a fifth column, to break the Earth Alliance from the inside. But the truth is quite different, though it's not revealed in full here: during the torture/interrogation of Sinclair, he was exposed to a Minbari sacred object, a triluminary, that glowed with intense light in close proximity to the prisoner. Moreover, one of the interrogators, the members of the Grey Council, was Delenn herself. The flashback to that revelation, one of the many details that were erased from Sinclair's memory, comes back through the use of drugs and mental manipulation operated by the two unknown men and also marks the moment when the Commander manages to escape his captors and flee through the station's corridors, in a hallucinatory haze. It's only through Delenn's intervention that Sinclair finally stands down, sliding into unconsciousness.
The episode raises a number of unanswered questions about the Grey Council's findings, and the reason not only for their surrender but for the series of following events, like the co-founding of the Babylon stations as focal points for diplomacy, or Delenn's choice of abandoning a prestigious place on the Council, Minbar's ruling body, in favor of a lesser posting as ambassador on B5. The fact that a higher-ranking Minbari, visiting in secret, orders her to kill Sinclair should he ever recover his memory, only adds more mysteries to an already convoluted puzzle, which will not be solved for quite some time yet.
Lies and deceptions are at the very core of this episode, as foreshadowed by a conversation between Sinclair and Garibaldi at the very beginning:
Sinclair: "Everyone lies, Michael. The innocent lie because they don't want to be blamed for something they didn't do, and the guilty lie because they don't have any other choice."
Delenn lied when the Minbari assassin – in the pilot episode – told Sinclair "There is a hole in your mind": she then defined the sentence as a peculiar Minbari insult, which now takes on a new, and more sinister meaning. She also lied about her rank and role in the war – in a previous episode, asked about it by Dr. Franklin, she smoothly evaded the question; it's easy to wonder if she lied to her visitor as well, assuring him she would kill Sinclair if he ever discovered the truth: her words and the expression on her face didn't match at all.
On the other hand, Sinclair himself lied about recovering the memories of his missing 24 hours, at least in part. Impossible not to recall G'Kar warning about people not being what they appear, and also the Soul Hunter's warning about the Minbari using Sinclair, or his wonder at Delenn's plans gleaned from the observation of her soul.
Finally, some light is shed on the survivor's guilt that clearly plagues Sinclair and now it's easier to understand his flirting with death every time he can. At this point in the story, he becomes a man in search of answers, and a man with a mission – where this will lead him, and us, only time will tell...