 Just when they find a window big enough for them to squeeze through, a nearby Rakweed plant unleashes its spores, but just before it strikes Rani and Clyde, the school bell starts ringing, destroying the Rakweed.They then realise that the Rakweed's weakness is loud noise, which disrupts its communication signals and prevents it from growing, thus killing it instantly.After escaping from the Blathereen, Sarah Jane returns to find Luke on the brink of unconsciousness.