plot thickens

cliché A situation or set of circumstances has become more complex, mysterious, interesting, or difficult to understand. A: "This whole time I presumed he was working for my father, but it turns out my father has never heard of him!" B: "Ooh, the plot thickens!" Now the plot thickens, as police have opened a line of inquiry into the governor's whereabouts on the date of the incident.

Things are becoming more complicated or interesting. The police assumed that the woman was murdered by her ex-husband, but he has an alibi. The plot thickens. John is supposed to be going out with Mary, but I saw him last night with Sally. The plot thickens.

People say the plot thickens when a situation or series of events starts to become even more complicated or strange. The plot thickens when he finds diamonds worth 6m euros hidden in a box of salt in the dead man's room. At this point the plot thickened further. A link emerged between the attempt to kill the Pope and the kidnapping of the American. Note: This phrase was widely used in 19th century melodramas, or popular plays that involved extreme situations and extreme emotions, and is now used humorously

The situation is becoming increasingly complex. Originally the term was used to describe the plot of a play that was becoming byzantine in its complexity; it was so used by George Villiers in his 1672 comedy The Rehearsal (3.2). It was repeated by numerous writers and became particularly popular in mystery novels, from Arthur Conan Doyle’s A Study in Scarlet (1887) on. Today it is often used sarcastically or ironically of some situation that is needlessly complex but scarcely meets the description of a sinister plot.