From Dublin Zoo to London Zoo, we're moving across the water with Sarah Lancashire this eve, as the camera crew returns to Regent's Park, and the country home at Whipsnade. It's all go this eve as Prince Philip arrives to open a brand new tiger enclosure. Everyone's hoping that the two of the animals will mate, giving the zoo its first tiger cub for 15 years. Will the Royal seal of approval send them on their way? We'll also be catching up with a pregnant Galapagos tortoise, and a chimpanzee who has a bit of tough time ahead.