Carli and Gypsy, the two newest chimp hooligans join the boisterous bachelor group, and Jim and Alison are on a rescue mission to Hungary to collect stump-tailed macaque Koko, who has been living in a pet-shop cage for 20 years.
Chimpanzee Charlie has to undergo emergency dental surgery, but the damage is worse than expected. Ro-Ro has trouble feeding her new baby. Chimp Seamus has failed to make any friends in Hananya's group.
Orphaned baby orang-utan Joly arrives at the park from Moscow, but her new housemate Hsiao-Ning is not pleased to see her. Plus, there's another new arrival as orang-utan Ro-Ro gives birth, and animal manager Jeremy captures the moment on camera.
Keeper Mike is on a mission in Moscow for a baby orang-utan called Joly, while back at the park her future home has been built. Meanwhile, in Paddy's chimp group, Eddi has a `toddler tantrum'.
There's a challenge for the staff as four chimps `move house' on one day in the park's biggest move around yet, baby chimps Ash and Rodders have breakfast at home with keepers Emma and Paul, and a Russian orang-utan orphan needs a family.
The nursery chimps get the better of animal manager Jeremy, and there's tension when a baby woolly monkey is born, but is rejected by its mother.
Alison looks forward to the prospect of baboons being at the park, while recently arrived marmoset Clyde, rescued from the pet trade, braves the great outdoors for the first time.
A visit from the vet awaits one of the park's strangest residents, while the small monkey team lose the battle to save tragic marmoset Koba, who had been taken out of the pet trade.
Orangutan Silvestre arrives in Switzerland to be the leader of a small group, and Alison decides the best option is to separate Sasha and Kangoo so they can have a chance at a fulfilled life.
Infighting in one of the capuchin groups leads to Louis having to undergo surgery while the cotton-top tamarin Mo loses their mate, Uncas, only to end up gaining a new friend.
The team at Dao Tien in Vietnam cares for a rescued douc monkey, two golden-cheeked gibbons take to the trees, and a slimmed-down loris enjoys success in its search for a mate.
Orangutan Silvestre undergoes a health check in preparation for moving to a new home, Sasha takes a trip outside for the first time, and Gismo's capuchin group play in a pit of pinecones.
It is vet day for some of the primates, and Nelly the loris causes some concern during the checkup. Meanwhile, Sasha the chimp gets to know some of Bryan's group while Teo the gibbon tackles some hanging feeders.
There are plenty of comings and goings at the park as a marmoset family heads to a new home, Tya returns looking for love, and the Barn Woollies welcome baby Xenia to their tight-knit group.
Dr Alison Cronin and animal manager Jeremy return from a trip to Argentina with Sasha and Kangoo, two chimpanzees are given a new home at the park, and Tuan's orangutans receive a treat.
Alison and Jeremy prepare to fly Sasha and Kangoo from Argentina to Dorset, which means crating and loading them in the middle of the night.
Alison and Jeremy travel to Argentina to meet two chimps as they prepare to bring them back to Dorset. The team attempt to sort out the macaques' hierarchy problems.
Chimp Bryan has a trip to the dentist to remove a rotten molar, and Lee Butler returns to Vietnam to assess repairs needed at Monkey World's sister sanctuary.
The primate care staff move more than thirty capuchins in a day, the chimps react to a fallen tree and the guenons finally get to try out their revamped home.
Vet Nic Masters uses high tech diagnostic equipment to examine health issues in some of the park's smaller primates, including capuchin Louis and patas monkey Penelope.