Expanding on @Ian 's answer...
This is quite soon after the beginning of the game. The white queen is out (not dead, I mean it is out of its position, free to move), so one white pawn is also out. Gus is the black pawn in front of the black knight, and Fred is the next pawn, which is in front of the black bishop. Both pawns are on the 'king-side' of the black army, and have not moved yet. Both sides may have made trivial moves to reach this setup.
When Gus decided to move far away from the cavalry, he saw an enemy
coming toward his camp.
Gus moves 2 steps forward. White makes a move with the queen bringing it directly in front of Gus (no space).
Fred also saw the enemy, and did his best to protect Gus, but because
of his love for his friend, his country immediately lost the entire
As Gus is in danger of the queen, Fred moves 1 step forward to protect it. The queen moves to the edge of the board (adjacent to Gus), and gives a check along a diagonal line to the black king. This is also a checkmate.
- There should be other ways to answer this question, I've just given one of the simplest ones.
- Someone who has more time could please add an image to clarify the answer?