Geriatric Gerald is rushed to the operating theatre, having recently lost weight and developed swellings on his body. Alison enlists an unusual helper to test a tracking device as she prepares for an important trip to Vietnam, and baby golden-cheeked gibbon Mikado moves in with foster mum Alex.

Oshine is introduced to the youngest members of the nursery, Lingga and Dinda, and animal director Jeremy hopes the encounter will be more successful than the orang-utan's disastrous meeting with foster mum A-mei. Meanwhile, with the boss otherwise occupied, there is a free-for-all at Hananya's when the chimps are given a large donation of fruit.