Whilst Dad is stuck in the desert, D.O.R.I.S. tries to give Cosima and Big Lizard a lesson on friction. As things begin to heat up, a creature steals Cosima's only means to locate Dad!
Source: CBeebies
Series 1: 18. Dad's Birthday
When Cosima wrongly accuses Big Lizard of eating Dad's birthday cake, he vanishes. Has he run away, or is he planning a special surprise to save the day?
14-07-2025
CBeebies
Series 1: 27. The Day Ammon Overcame Her Fear
Ammon gets spooked by a tiny insect, but overcomes her fear to rescue Cosima and Big Lizard from the rapids.
14-07-2025
CBeebies
Series 1: 31. A Medical Emergency
Whilst playing doctors, Cosima discovers an animal with no heartbeat! Can Cosima and Big Lizard save the poor creature with Dad's medical kit?
13-07-2025
CBeebies
Series 1: 34. The River Picnic
Cosima and Big Lizard go paddleboarding, but Dunk and the river creatures are behaving strangely. Could it be something to do with Dad's desire for a cup of tea?
13-07-2025
CBeebies
Series 1: 30. Dad's Drone
Big Lizard wants to have a go with Dad's new drone, but first he has to prove that he can go a whole day without breaking something precious. Good luck, Big Lizard!
12-07-2025
CBeebies
Series 1: 33. After The Storm
After a storm passes overhead, many creatures turn up in surprising places and need Cosima and Big Lizard's help. But try as they might, the friends can't find poor Rex.
12-07-2025
CBeebies
Series 1: 17. The Cocoon
A dragonfly steals a bee cocoon that Cosima had vowed to keep safe. Cosima and Big Lizard give chase, leading to a surprising solution with a vacuum cleaner and some sticky vines!
11-07-2025
CBeebies
Series 1: 26. Happy Proximas!
When it unexpectedly snows, Cosima decides it must be Christmas! Rex disrupts her festive preparations, but it doesn't stop the family having a perfect 'Proximas'.
11-07-2025
CBeebies
Series 1: 16. Crystals!
Big Lizard has found an epic crystal, and Cosima is jealous. Their squabbling reaches its peak at the top of the volcano! Will they learn to share before it's too late?
10-07-2025
CBeebies
Series 1: 25. Cosima In Charge
Dad has left Cosima in charge for the day. It seems like an excellent opportunity to have a massive party! What could possibly go wrong?
10-07-2025
CBeebies
Series 1: 48. How To Speak Lizard
When Dad's Lizard Translator malfunctions, Cosima is carried away by a giant beetle! Cosima and Big Lizard realise they don't need to speak the same language to be best friends.
14-06-2025
CBeebies
Series 1: 12. All About Home
Cosima is so excited to tell Big Lizard about her life on earth that she doesn't realise he has something exciting to say to her.
04-07-2025
CBeebies
Series 1: 45. Prank Day!
Dad and Cosima both think they're the best at pranking. Their prank war quickly spirals out of control, until Big Lizard finally reveals Proxima's real pranking champion!
09-06-2025
CBeebies
Series 1: 19. Best Friends Forever
Big Lizard is jealous of the vacuum cleaner and hides it from Dad and Cosima. Ammon decides it's her new best friend, whilst Cosima reassures Big Lizard that he will always be h ...
02-07-2025
CBeebies
Series 1: 1. The Day We Landed
Whilst exploring deep space, a meteor strikes Cosima and Dad's ship! After crash-landing on the unexplored planet of Proxima, Cosima makes a new best friend called Big Lizard.
29-06-2025
CBeebies
Series 1: 22. The Sea Meteorite!
When a meteorite splashes into the sea, Dad and Cosima cause problems by claiming it in the name of science, against the wishes of the sea creatures.
07-07-2025
CBeebies
Series 1: 23. Astronaut Health Check
Dad needs some training to pass his astronaut fitness test. Cosima and Big Lizard put him through his paces! When Rex gets into trouble, Dad’s hard work finally pays off.
08-07-2025
CBeebies
Series 1: 30. Dad's Drone
Big Lizard wants to have a go with Dad's new drone, but first he has to prove that he can go a whole day without breaking something precious. Good luck, Big Lizard!
12-07-2025
CBeebies
Series 1: 49. A Big Day Out For D.o.r.i.s.
Dad gets trapped in the shower when D.O.R.I.S. decides to visit the sea. Can Big Lizard and Cosima stop her before she does herself permanent damage?
15-06-2025
CBeebies
Series 1: 50. The Earth Probe
Finding an earth probe makes Dad homesick. When Big Lizard accidentally destroys it, Cosima knows what to do. She recreates the contents - Proxima-style!
21-06-2025
CBeebies