Tiger Aspect Productions for BBC Two, 26 July to 11 October 2009 (12 episodes in 1 series)
Tiger Aspect Productions for CBBC, 24 October 2009 (Compilation show)
With their dad away for a couple of days, children are filmed in their family home for a TV programme called 'Mega Nanny'. In Mega Nanny, a children's nanny comes to stay for a few days, however unlike other nannies, Mega Nanny is the ultimate when it comes to anti-parenting, encouraging noise, mess, and general chaos. Unknown to the children however is the fact that Mega Nanny is an invented TV programme, and their dad is actually much closer than they think. Little do they know, Mega Nanny is their dad, who, after having spent several hours in make-up, and with the use of prosthetics, to change his appearance, now looks like a somewhat elderly woman.
Over the course of two days, dad, as Mega Nanny, with help from mum and the host must complete several tasks. Often these tasks see dad having to encourage the children to break several of his own rules. Other tasks are solo challenges, such as having to enter the house without wearing the Mega Nanny wig, and having to retrieve it without being spotted. For each task dad successfully completes, the children win a family day out. During the course of the tasks, in the guise of Mega Nanny, dad also has the opportunity to learn more about how the children feel about life at home, and how they feel about dad himself. Turning somewhat serious for a children's programme, this can often be quite revealing, some times resulting with dad being quite shocked about what the children have said.
At the end of the two days, Mega Nanny's true identity is revealed, before dad must take part in one final task - a quiz to prove he has got to know his children better over the two days. If he passes, he can join the family on their day out, if not, he must help the children with their homework for a month.