S1·E20 Pingu in the Ice Cave

Pingu and his parents are doing odd jobs when Pingo comes over and asks Pingu on a playdate. The two go off hysterically. They play with their ball and have fun at first, but get a bit carried away, and the ball goes off into an overhang in the ice. When they try to retrieve it, they fall through a sort of trapdoor in the ice and into an ice cave. The entrance collapses above them, and they must find another way out. After looking around in the dripping, echoing caverns, they see a slope to the surface - which happens to be on the other side of a deadly chasm. Pingu manages to cross by swinging on a rope, which comes off as he gets to the other side. He then lassoes the ropes onto a small stalagmite next to Pingo, and tells Pingo to hang onto it and shuffle across the chasm, with Pingu holding onto the rope on the other side. But Pingu begins to slip due to Pingo's weight on the rope and he nearly falls. Pingu quickly tugs on the rope, pulling Pingo back up unharmed and catches him just in time, and the two crawl out cheerfully to the surface.