Chlamydomonas can react to intense light or mechanical stimuli via a shock response, whereby its two flagella change temporarily their beating and their state of synchronisation. How does flagellar synchrony change during these transitions? In a new work, we do this via a wavelet-based phase synchronisation index. The results suggest that cells might transition between standard and shock flagellar beating by simply modulating the relative importance of “harmonic states” that normally coexist. The work was led by Lucas Federspiel, from the group of Antoine Allard and Françoise Argoul (LOMA, U. Bordeaux). It was a pleasure to have the opportunity to help them and be part of this exciting project!