Rodney's talk of environmental pollution brings him a strange ally when Del becomes a friend of the Earth. Of course, he's got a scam going and it involves a joint venture with the Water Board - but they are a silent partner!

At Del and Rodney are strapped for Christmas cash. To make matters worse, while Cassandra finally has her promotion, Raquel is suffering from post-natal depression.

Rodney is concerned that Del has lost his drive. When confronted, Derek explains that on top of his woes, the council have approved his application to buy their flat in Nelson Mendela House, doubling the rent. On top of that, Grandad's allotment has become a health hazard and he has to clear it.

While clearing the allotment Del discovers several barrels of yellow liquid. Enlisting Trigger and Denzil, they are disposed of during the night.

Finally spotting a gap in the market, Del decides to bottle tap water and sell it as Peckham Spring Water.

Back in the money both couples enjoy a romantic evening... until they see a news flash about a major water contamination, caused by Del's barrels.