Grizzy has anticipated everything for his birthday and plans on spending a peaceful day in the cabin doing his favorite activities. But when the Lemmings find out it’s Grizzy’s birthday, they devise other plans. Farewell, Grizzy’s peaceful day - make way for the Lemmings’ party surprises!

Grizzy finds a giant home cinema screen that transforms his favorite documentary film into an incredible light and sound experience. But his pleasure is ruined by the Lemmings’ fiesta. While he chases after his housemates to destroy their disco equipment, he discovers with astonishment that Asian clones of himself and the Lemmings are also engaged in a high-speed pursuit.

Grizzy and the Lemmings fight over a jar of Yummy which is mysteriously sucked up into a strange gravestone locked with a puzzle. Grizzy smashes open the gravestone but it contains another box made of unbreakable wood protected with a codex system. Our characters crack the code and are sucked into the box in turn. They discover that to get out, they will have to resolve a series of new puzzles, each one more complex than the last.

As the Lemmings rummage through an abandoned delivery tricycle filled with strange objects, they discover a delicious treasure: Yummy-filled Chinese brioches! Grizzy steals their tasty bounty and heads off to enjoy it alone in the cabin. The Lemmings find a mask in the tricycle that terrifies anyone who looks at it when it’s being worn by someone. The Lemmings intend to use their horrific new power to recover their stolen treats.

The Lemmings lay hands on an ancient console that lets you play life-sized games in the real world. The console emits magical streams of energy that randomly pick avatars to confront one another. Grizzy is chosen as the hero. He must leap onto platforms and confront both enemies and a fearsome leader: a panda equipped with bamboo sticks. The Lemmings are obviously in control of the joystick!

The Lemmings discover a new passion: magic Chinese lanterns that they use for sound and light performances. Grizzy is not very enthusiastic about this new electric activity which keeps him from sleeping. While Grizzy thinks that he got rid of their lanterns, the Lemmings discover new high-tech lanterns capable of making even more of a ruckus.

The Lemmings catch a grasshopper that can give you whatever your heart desires in abundance. All you need to do is set the grasshopper on its head while concentrating hard on what you want. As discretion is not the Lemmings’ strong point, Grizzy ends up understanding where their profusion of toys is coming from. Grizzy decides that it’s his turn to hunt down the grasshopper.

The Lemmings find a crate of cell phones: there’s one for everyone. But before being able to play with their new toys, they need to charge the batteries. This operation uses all the electricity stored in the cabin’s solar battery and prevents Grizzy from watching TV. Grizzy soon realizes that this is the least of his worries, for living with the Lemmings and their phones is a guaranteed nonstop stream of noise pollution.

Grizzy and the Lemmings fight over a large silkworm that produces an extremely soft and resilient elastic thread ad infinitum. The Lemmings consider the worm the ideal game companion, but Grizzy needs the worm to make his knitwear. To become masters of the silkworm, the close enemies will go to harsh extremes.

An integrated circuit containing an artificial intelligence accidentally connects to Grizzy’s stuffed teddy bear, which comes to life like a modern-day Pinocchio. Grizzy educates the chip until it decides to connect to the Lemmings’ robot to play with them. When the AI becomes a teenager, it is no longer interested in either Grizzy or the Lemmings and prefers using a smartphone to keep learning. Grizzy and the Lemmings join efforts to try and reset the chip’s memory and relive its childhood phase over and over.

Grizzy and the Lemmings, who are both starving, discover a temple dedicated to an ancestral brioche. According to the book lying open inside the temple, to obtain a perfect brioche you must gather three gold ingredients and set them on the altar. When the panda idol who guards the temple receives the offering, the person will receive his favorite food in abundance. Grizzy and Lemmings set out to find the sacred ingredients but there is no question of working together. May the best critter win!

Grizzy and the Lemmings are hungry! While fighting over a jar of Yummy chocolate spread, the jar is destroyed. But Grizzy discovers an ingenious manner to recover the remains of another Yummy jar using instant Chinese noodles as inspiration. The result is delicious. Grizzy and the Lemmings will once again fight over this new Yummy-based recipe: Choco-noodles.