Sonny Hammond is a Park Ranger. After an accident involving a dangerous helicopter rescue, he is sent to work in the city. He and his twin children Jerry and Louise (Lou) are unhappy at being cut off from the bush and most of all from their wonderful kangaroo Skippy. Skippy disappears from her usual bush haunts, pining for her lost family. Two of the Hammonds’ friends mount a search for her - Kate the vet, and Thel McGee, proprietor of Habitat, a small animal-based tourist attraction near the National Park. Kate and Thel, however, decide that only theHammond twins can help in the search. Skippy is found by Jerry and Lou, Sonny becomes a partner in Habitat, and the Hammonds are off to a new life.

A lonely and unhappy boy wanders into the Hammond twins’ lives. But he’s not only lonely - he’s a menace. Clever with electronics, he makes the lives of Lou and her friends a misery by rigging up fake spiders powered by batteries, and spins Jerry tales that an old mill near the Hammonds’ place is haunted. He also talks Jerry into sneaking out after dark to see the ‘ghost’. Jerry is in dead trouble when Sonny discovers this. Then Lou makes a discovery too - the ‘ghost’ is actually a series of mechanical and electrical tricks rigged up in the mill. She turns the tables on the boy who did it by taking him unawares with his own devices. It’s also made her realise how smart he is, and she! asks him to rig up something special for the local Halloween celebrations.

Bird smuggling is a serious crime in Australia, and when it comes home to Habitat, it takes the combined efforts of the twins, Sonny, and Ranger Dave to prevent it. There are two men involved - one would do anything for the ‘big bucks’, and the other is a local who provides a boat to get the birds down river to a ship waiting to take them overseas. Skippy, Lou and Jerry combine to release the men’s original prey, and the criminals get the desperate idea of stealing the collection of native birds out of the aviary at Habitat. But when there are no bird calls to wake the Hammonds and Thel next morning, they are all immediately on to the case, and quick action sees the criminals caught on the jetty at Habitat, with Ranger Dave on hand, and the men’s boat drifting helplessly in the middle of the river, with a little help from Skippy releasing the rope that tethers it. Here’s one lot of birds that will never leave Australia!

Lou and the teenager Chris go to Gorman’s Park to get proof that the flashy entrepreneur is mistreating his animals. Jerry, with the instinct that comes from him and Lou being twins, gets the same idea and turns up there as well. One of Wally World’s security guards catches them all and Gorman uses the threat of prosecution to try and blackmail them into selling Habitat to him. The security guard however is sym!pathetic to the kids and gives them photographic evidence that they need to expose Gorman’s misdeeds and to get his threatening hands off Habitat. Skippy and her friends triumph when Gorman is taken in on animal cruelty charges, and Chris decides to move on.

Lou does well in a school science project that involves throwing the voice by simple electronics. But her cleverness backfires when she attaches the device to Skippy’s collar and plays tricks on the local storekeeper, Jack. It looks as though Skippy is actually saying the wor!ds, and two genial no-hopers, Alec and Bill, overhear the trick and think they’ve found a talking kangaroo! They’ll make millions!! They steal our heroine, and Lou and Jerry, aided by Tyke, a little terrier who hangs around the store, have to give chase to get their favourite back.

Lou is discontented when Thel won’t let her row across the river to the fish markets. And she causes trouble for everyone when she takes Thel’s dinghy and gets into dangerous currents in the middle of the river. Skippy alerts the father of Lou’s friend Elyse, who is a fisherman. He saves Lou but wrenches his shoulder and can’t take his boat out. Elyse and Lou get the idea that if they spend the day out in the boat catching fish they’ll make it up to him. But who will help them? The answer is Elyse’s scrawny 14 year-old brother Kenny. Kenny wants to follow in his father’s footsteps, but his father doesn’t think he’s suited to the hard life of a fisherman. Jerry raises the alarm when he! realizes the boat is gone, and a search follows. However Kenny and the two girls turn up trumps. They come back safely with a load of fish in spite of the fears of the adults and Skippy.