Darzee’s wife helps Rikki-tikki in his battle with Nagaina.
Rikki had already killed her husband Nag and all of her eggs except one. He used the last egg to lure Nagaina away from Teddy and the other humans. He knew that she was mad, and he was trying to disorient her. He was successful! She followed him in a fit of rage, but the danger was not past.
As Rikki raced into the garden, Darzee was singing but his wife decided to help.
…Rikki-tikki heard Darzee still singing his foolish little song of triumph. But Darzee's wife was wiser. She flew off her nest as Nagaina came along, and flapped her wings about Nagaina's head.
Rikki believed that if Darzee had helped distract Nagaina he would have been able to get the jump on her, but Darzee was always more foolish than his wife.
This incident shows that no matter how brave and skilled they are, heroes need help. Rikki did defeat Nagaina due to his cunning and strength, but he could not have done it without Darzee’s wife’s help.