The ancient Roman scholar how tell me the elder relied an unbelievably story in which the little hundreds of pages long was written on parchment paper and inserted into a shell of a walnut William Shakespeare later referenced his story when when his character Hamlet uses a phrase in a nutshell today to describe something that is compact what is the meaning of the illusion in the sentence below so in a nutshell that's the story of my mouth month long trip to Iceland

The illusion in the sentence "so in a nutshell that's the story of my mouth month long trip to Iceland" is a metaphorical reference to something being compact or concisely summarized. It suggests that the speaker is providing a brief and condensed version of their month-long trip to Iceland, encapsulating the main details or highlights.