For several months, Mika has been finding strange things on his motorcycle every day: red ribbons, coins, locks... Until a mini-cadenas hidden in the chain of her engine almost causes a serious accident. Determined to find the culprit, she films her bike remotely with the help of her friends. Soon, everyone's fantasies and projections cloud the issue. Harassment, flirtation or revenge? Is the situation romantic, romantic or threatening? Mika and the gang investigate.