 After an article in the paper about a fire in another private students  home, Jeanne realizes it s time to invest in legally required fire-extinguishers etcetera. After a hefty quote from a professional Jef decides he needs to save enough to buy a humidifier for his plants hothouse, by doing the job with Odilon, who also agrees to send a colleague as fake fire inspector so Jeanne will buy their story, while Jeanne asked someone else to scare Jef into hiring a professional firm, and a real one responds to Ria s notification, but who is which one? Meanwhile Jo and Betty exchange fire - and water pranks.