S37·E54 Episode 4938 (Fri 14th Mar 2008)

Nicola tinkers with the electric train control box. David pleads with her to give up her idea, but Nicola is stubborn. Nicola waits expectantly when Donald later picks up the 'live' switch but nothing happens and she realises that David has fixed it back. Nicola vows to continue her murder attempts and a desperate David confesses all to Donald, revealing he doesn't want to see Donald dead and Nicola in jail.