One by one, the others remain behind to hold off their enemies, and only D'Artagnan reaches Calais, where he discovers that Lady de Winter has seduced Buckingham and gotten the diamonds.
The others remain behind to hold off their enemies. This is one by one. One by one D'Artagnan reaches Calais. This is only. Lady de Winter has seduced Buckingham. Lady de Winter has gotten the diamonds. He discovers this.