Forget "Curiously Refreshing." Leave that to the days when Commander Whitehead was on every television screen touting Schweppes Tonic Water.
(FYI: Commander Edward Whitehead (1908 – 1978) was a British Royal Navy officer, a veteran of the South Pacific campaign, and at one time the President of Schweppes (USA). He is better known as an advertising representative of Schweppes in a campaign created by Ogilvy&Mather Agency in 1955 which ran through the 1960s.)
It's the new century and Cooky Cat is all up into the mystery of things. Also, it happens to be G&T weather. Gin and Tonic, darling, if we have to spell it out.
Here are the quintessential ingredients to give your G&T a most haunting deliciousness. First, let's step up tonic-wise. Top of the line, Fever-Tree Tonic Water. (Tops in price too.)
If you're wondering about the Gin, well we leave it to you. Our Botanist from Islay is too precious for anything other than neat or in a very dry martini. Bombay or Beefeaters will do the trick. A friend suggests Hendricks, but that too is rather nicey and pricey; best savored on its own, as with the aforementioned Botanist.
Now that you've upped your G&T game with the Fever-Tree Tonic, let's consider two additions to get the haunting going spookafragistically.
Either or, but never both: Stirrings Blood Orange Bitters or St. Germain Liqueur crafted with hand gathered elder flowers. The fourth taste that either one of these will contribute to your G&T will raise your refreshing beverage to a level that is, as they say, something completely different.
Just don't put in too much, just enough so you can get a hint of a taste of it in there without being able to put your finger on it. (Like a ghost, get it; "haunting".) Or, like the inestimable Ms. Julia Child would admonish about overdoing the nutmeg: "You don't want so much that people can say, 'Nutmeg!'"