To find all the puzzle pieces in Level 6-K, Perilous Passage in Donkey Kong Country Returns, follow these detailed steps:

1. First Puzzle Piece:
– After leaping to the second platform that drops in the center, remain on it until another platform drops on the right.
– The first puzzle piece will be exposed on this new platform.

2. Second Puzzle Piece:
– Roll jump at the block with the ornate design of a monkey in the upper left corner of the first section (right before the horizontally moving platforms with purple spikes).
– The block will disappear, revealing the puzzle piece behind it.

3. Third Puzzle Piece:
– In the area where electric bugs are chasing you, look for a block with an ornate design of a monkey on it, located just to the left of the trampoline.
– Enter it from the right side to find the puzzle piece.

4. Fourth Puzzle Piece:
– In the same area where you’re dodging electric bugs while bouncing between two trampolines, jump onto the second platform on the left wall.
– From there, jump up into the wall to find the puzzle piece.

5. Fifth Puzzle Piece:
– The next platform on the right side has a similar compartment hiding the last puzzle piece.
– Grab this piece by entering the compartment from the right side.

### Summary of Locations:
– Puzzle Piece 1: Exposed on a platform that drops in the center.
– Puzzle Piece 2: Revealed by rolling into a block with an ornate monkey design.
– Puzzle Piece 3: Hidden in an area with electric bugs, accessible from the right side of a trampoline.
– Puzzle Piece 4: Located on a platform on the left wall, accessible by jumping up from the second trampoline platform.
– Puzzle Piece 5: Hides in a compartment on the right side of a platform.

By following these steps, you should be able to collect all five puzzle pieces in Level 6-K, Perilous Passage.