Ever wondered why there have been so many urban myths and songs dedicated to LSD? Molecular dynamics (MD) simulations suggest that LSD’s slow binding kinetics may be due to a ‘lid’ formed by extracellular loop 2 (EL2) at the entrance to the binding pocket. Put simply, the findings, published in Cell, have now showed that once the LSD compound catches, part of the serotonin receptor folds down over it, meaning that it is held tightly in place and thus allows the drug to perch in the brain for several hours, even up to 12 hours at times.