The living room on the third floor of the block of flats in Red Pyjamas Street was quiet. Only one household member was awake: Zenon, a cactus with a lush imagination and thorns that quoted the classics themselves. This was no ordinary cactus - Zenon knew the neighbourhood's secrets best and had his own club for potted plants. The club, Roots of Reason, met every Thursday when the owner, Mrs Janina, was away for a night of yoga. Then orchids, a Boniface ficus, three ferns from the kitchen and a geranium from the balcony would quietly slide off the windowsills into the living room. Zenon, as chairman, began each meeting with the slogan: "Long live chlorophyll!". That evening, there was a smell of excitement as a new guest arrived unexpectedly - a succulent named Bryś, a newcomer from an exotic pot bought on promotion in a garden shop. Nugget looked inconspicuous, but whispered that he knew a secret way to grow roots in the floor and.... contact with neighbours from other flats! The plants shook their leaves with excitement. Zenon asked Brysia to show his trick, but then a strange rustling sounded in the corridor. The ficus Boniface went pale (as pale as a ficus can go) and the ferns started whispering about legends of pot-busters. The door slowly swung open and.... something very, very unexpected stepped inside. What was it? And will the Roots of Reason Club survive this nighttime expedition...?