The title of this work, Regula, refers to all kinds of imaginable regulations and restrictions about social distancing during the coronavirus pandemic. Suddenly, we could not see, touch or hug our loved ones, especially elderly relatives. To fix this problem, a 'cuddle curtain' was introduced in some care homes. It is simply a big plastic sheet (often made out of a shower curtain) with improvised armholes that allow individuals to embrace without direct contact. In this work, a thunder sheet is placed in the middle of the players, representing a 'cuddle curtain'. The musicians are separated but, at the same time, in contact with each other, playing it from both sides. Thunder sheet also has its ominous presence; should we sigh for relief after the pandemic, or was it merely a storm warning of something else lurking in the future? TR, 2023