Ben Fogle and Kate Humble are back for another sun-filled summer series, following the extraordinary lives of the exotic animals at Longleat Safari Park and the keepers who look after their every need. Today, we find out how the keepers' continued vigilance and dedication to the animals' welfare can alert them when something seems to be wrong.

There's another milestone for Hazel, the first southern koala born in Europe. She has to be separated from her mother for a short period. This is to ensure that the keepers earn the baby's trust before she becomes impossible to work with. Without this, the park wouldn't be able to perform their routine and important health checks. But can the keepers separate Hazel from her mum for ten minutes without distressing either of them?

Also, one of the keepers has noticed that the park's monitor lizard has a worrying issue with his spine. A specialist osteopath, who takes care of zoo animals that suffer from muscle or joint problems, is brought in to investigate. If he can't treat the lizard, the keepers will have to resort to giving him medication, a dangerous job for those who look after him. The osteopath decides to use laser therapy on the lizard, but will it work?

Elsewhere in the park, it's not just the animal keepers who are kept on their toes. The housekeepers of Longleat have their hands full hunting for carpet beetles that munch away on natural fibres like wool and silk. Kate heads inside to help in one of the house's 135 rooms. Ben celebrates a white-fronted brown lemur's 28th birthday, but what type of cake does a lemur enjoy?

Megan McCubbin finds out how the keepers train the nervous bongos to accept medical procedures like medicine and blood tests. Hamza Yassin has been given a task by the head of animal operations: to record the number of different wild birds he can spot in the park in just an hour. It's a useful barometer of the diversity of native species in the park.

Ben Fogle and Kate Humble are back for another sunny summer series following the remarkable lives of the exotic animals at Longleat Safari Park, and the keepers who care for their every need.

Today, we find out that building a relationship with an animal takes a huge amount of work and commitment, but the results can be spectacular. Over the last few years, Animal Park has followed the park's efforts to gain the confidence of the hyenas. They have had a history of being skittish and staying away from humans, but the keepers have worked slowly to gain their trust. This week, the park needs to tidy and maintain their enclosure, so the hyenas can remain active and in good health, but they can only do it if they can persuade the hyenas briefly into their house. It's a nerve-racking experience for the keepers as one false move could mean losing years of trust-building with the hyenas.

Also, the keepers have to carry out essential health checks on the park's new red pandas. The animals spend most of their lives in the treetops, so it's hard to see their feet, but the keepers have a plan. They are building a clever gadget that will show each panda's reflection, but only if they can be persuaded to stand on it. How will the keepers encourage these famously nervous animals to come near it?

Elsewhere in the park, Kate helps with the keepers' plans for a lads' day out for the lions. They are putting one of the prides into another lion's territory in an attempt to analyse the current pride structure. Ben challenges the donkeys with a dinner-time puzzle, Megan helps the keepers give an Argentine tegu a bath, and Hamza has been given a challenge to film one of the park's rhino horns very close up. It's an easy job when the subject is still, but the rhinos rarely are.