S1·E6 Episode 6

Despite what Tama and Royce thought about her not going back, Jo does anyway. Using his computer at home, Tama finds a site which has formula's to neutralise the toxic waste. Meanwhile, Catherine has decided that she has had enough and tells the rest of the family that she is going to resign as school principal. While doing some more research, Tama finds a report about toxic substance which mentions Sir Ivor from 1919. Nicholas has been locked in his room, and wants Jo and Louisa to help get him out. Sir Ivor refuses to give back the signet ring to Nicholas.