Many European monastic orders are renowned for brewing beer, but they also have a reputation for crafting quality liqueurs, such as the highly sought-after Chartreuse.

Chartreuse is a complex liqueur composed of 130 herbal ingredients with a complicated and closely guarded recipe that is only fully accessible to two Carthusian monks in France.

They are the only people who can view the 17th-century manuscript that outlines the ingredients. Every generation, two new monks are selected to continue this tradition.

According to the 2005 documentary “Into Great Silence," the array of ingredients are already sorted by the brotherhood before being sent to their partner distiller.

However, many monks are part of the preparation and distilling process without knowing the full recipe. So, if anything happens to the chosen monks, successors are on standby.