To the Bitter End is the thirteenth episode and the finale of the first season of Angry Birds Stella
Gale gets herself trapped inside an active volcano in search of the elusive Golden Egg. Stella comes to the rescue, but as the temperature rises, can these two work together to escape without getting roasted?
The episode begins with Stella climbing up a coconut tree, collecting the fruit, when they feel trembling from an unknown source. Stella climbs back into the tree and notices smoke from the foot of the volcano in which Gale lives, suspecting trouble, Stella goes to the source of the smoke and the rumbling noises. The camera then cuts to the foot of the volcano, and the source of the noise and smoke are actually coming from the pigs drilling into the volcano wall at, of course, Gale's command. Gale goes into the volcano in pursuit for the mysterious golden egg. Stella, suspicious and perturbed, starts to question the pigs, but then realizes that Gale is in there and hearing the rumbling again and seeing the rocks fall, Stella realizes that Gale is about to get trapped. Stella then leaps into the volcano to save Gale, with Poppy trying to bit her tail in the process to stop her, but failed and Stella gets trapped in with Gale in a rock slide, making the flock and the pigs terrified.
The flock and the pigs then start to plan the rescue, meanwhile, Stella realizes that she's trapped and notices Gale clinging to a wall, and out of surprise, Gale face-plants onto the ground. Stella, still a bit angry at Gale for getting them into this situation, goes to the entrance and starts pecking at the rocks, failing. Gale then goes to the massive heap of boulders and removes a smaller rock, making a bigger one almost fall on Stella, resulting in a brief quarrel between the two birds before they notice magma closing in on them, they escape to higher ground.
Outside of the volcano, the flock and the pigs find a place to tunnel in and save the birds. Gale and Stella walk through a corridor that appears to be leftover ruins, depicting archaic scribes and the golden egg that Gale's sought after for so long, Stella sees this golden egg and realizes that Gale's change in personality was in result of this artifact. Gale and Stella walk across an old, wooden bridge and they're almost on the other side when they encounter a skunk, Gale hides behind Stella and she gets sprayed with the Skunks odor, Gale giving a short insult and Stella becoming more angry, but they immediately see that the skunk is cutting away at the ropes holding up the bridge.
Gale and Stella immediately run back to the other side, jumping to safety, and the skunk then runs away at the next trembling. Stella sees some sticks and is able to construct a hang-glider, and Gale contributes by using the cloth on her back to complete the contraption. Feeling scared at first, the two finally gather enough confidence to glide to the other side of the magma river, and they succeed, and the two birds feel overjoyed and close in amended friendship, but it doesn't last long as Gale eventually finds the golden egg with magma in quick pursuit. Gale goes into the chamber and runs towards the golden egg, but another tremor creates a gap for the egg to fall into, and Gale yells in agony until she sees that the egg is still safe. Gale turns back to see Stella on a lone rock in the middle of magma, and after a tough decision, Gale seemingly preferred the golden egg over Stella, leaving Stella heartbroken and preparing for the end, but then Gale comes back and knocks down a couple pillars, saving Stella. Stella then ends up on a platform with Gale, and they realize there's no where else to go, and Gale begins to cry alongside Stella as they prepare to face death. A few moments later, they hear another tremor and this time, a tunnel is made with the pigs' drill and Stella's friends come to the end of the tunnel where they see her and Gale. Seeing that there's a way out, Gale and Stella makes a run for it, but not before Gale remembers the golden egg and goes to retrieve it while Stella safely jumps into the hole in the wall, and turns back to Gale carrying the golden egg, leaving Stella horrified. Gale stares at the golden egg and laughs that she finally reached her achievement, while Stella watches rocks fall from the ceiling, where Gale is standing. After a few more moments of looking at the golden egg, Gale then looks at Stella and her friends for the final time with a happy expression before being crushed by rocks. Stella, witnessing this, attempts to go back in and save Gale, but Poppy succeeds at biting Stella's tail feather and drags Stella to safety. Stella and the flock run out to safety, but after seeing Gale failed to make it out of there with them, and witnessing rocks crushing her, this leads Stella to conclude that Gale was killed, and she's grief stricken. The pigs and the flock are filled with sadness and grief as the camera quickly pans to the top of the volcano, with a cloud of smoke in the shape of an egg briefly appears before ascending into the sky.