Premise: You're one of the last people in the town. Everyone else has fled on the government's orders, on threat of an unknown Enemy (yes, capital E).
Nightfall is technically proficient, featuring several good examples of parser conveniences. The player can use the "GO TO" command to navigate the substantial map, and there is an impressive amount of content to explore.
I found the sheer number of memories available slightly overwhelming, even if most of them appear almost… trivial. Memories sparked by visiting certain places for the first time are indexed for future reference, though not all of the memories turn out to be important for progressing in the story.
The swelling inventory is disambiguated, but in a way that shows off the underlying skeleton of the parser format. Items of the same kind are colour-coded, like one might find in a point-and-click game (does anyone even remember those any more?!), whose artificiality becomes more obvious the more time one spends with non-parser or more modern, naturalistic games.
I found it hard to suspend disbelief starting from the premise. The town in Nightfall has the air of an unimportant town caught in the thrall of international politics, a little like Salisbury was to UK politics in 2018. The game remains infuriatingly vague about specifics, though, and do not offer too much information payoff for following a lead. If anything, the character motivations struck me as being a bit threadbare. The player character appears to be motivated mostly by an obsession with the unnamed female character, whose motivations we never understand - we cannot even infer it from the PC's memories of her - until the ending.
Nightfall is a large and mostly well-constructed game. The espionage setting will be familiar to denizens of the parser format, and despite everything I could still enjoy the game. Recommended.
(This review was based on the IFComp version on IFDB.)