I enjoy reading this great Mermaid tale very much, which reminds me of Wilde's fairy tale in some way.

What's more, its descriptions are so wonderful and vivid, such as "a filigree of bubbles, to keep the contents of his stomach in its proper place and frilly knickers adorning the desktop lamp", etc.

However, I have difficulty in understanding this sentence: "He must have reached the point of no return when the walls come down and the performance takes him over."

I would be very appreciated if you could explain it to your reader. Thank you!