You enter Q&A through what looks like a 1960s industrial freight-elevator door on a quiet stretch of Sukhumvit Soi 21. There is no sign. The corridor inside has been done up to look like a train carriage from a Bond film. You walk through it to a thick velvet curtain. Then you are in the bar.
Inside: green leather, brass, low light, a fifteen-metre bar with one of the better back-bar selections in Bangkok and a team of bartenders in white jackets who clearly know what they are doing. Order the Mae Klong - Mekhong (Thai rum), lemongrass-infused vermouth, makrut lime, gum syrup. It is a riff on a Negroni Sbagliato that the bar has been refining for years and is the right opening drink.
Q&A is not the most ambitious cocktail bar in Bangkok. It is the most reliable. Two-and-a-half hours, three drinks, never a wrong note. On a Tuesday it is the kind of bar that makes you remember why you flew here.
Q&A opened in 2014 and has not significantly changed its concept since. The crowd skews international and slightly older than the newer Chinatown rooms - business travellers, expatriates, the occasional regional cocktail-bar pilgrim. The bar holds its line and refuses to chase trends, which is the reason it is still on Asia's 50 Best a decade later.