A businessman Mukhин had a painting by Goncharov, “Twilight,” stolen—one he bought recently at a Moscow exhibition. The motive looks unconvincing: from all the canvases, the thieves chose the least valuable one. Mukhин asks for help from private detective Tatyana Ivanova. Tanya finds out that at the Moscow exhibition of paintings titled “Twilight,” there were… two! And they belonged to brushes of two different masters. Continuing the investigation, Ivanova starts to think that the title “Twilight” is somehow mystical: as if, figuratively speaking, twilight is thickening around this case even more with every new fact—adding more fog…