Biscarrat and his companions halt in front of the grotto.
They are certain that the dogs have gone in, but are suspicious that they do not hear them. Each of the men calls for the dogs, but get no answer.
Biscarrat tells the men that he will go investigate the grotto. He goes alone, saying there is no point in more than one person risking his life.
After he enters, he feels the muzzle of a musket on his chest. At the same moment one of the servants brings his knife towards Biscarrat's throat, to be halted by Porthos, who refuses to have Biscarrat killed.
Aramis comes up to Biscarrat from behind and presses a handkerchief over his mouth, warning him not to say anything.
Biscarrat is taken aback. He thought Porthos and Aramis were in the fort.
Biscarrat swears not to tell his companions what happened, but also swears to try and stop them from similarly entering the grotto.
Biscarrat returns to his friends and is very reticent about what he has seen in the grotto. His friends, believing Biscarrat to be holding out on them, want to enter the grotto. He begs them not to enter, but they pay no attention.
Biscarrat waits while his friends enter, and presently there are sounds of gunfire.
The men stagger back cursing Biscarrat for not warning them of the ambush. Four men have been killed.
The men yell at Biscarrat to tell them who is in the grotto. One man, wounded to the death, demands Biscarrat reveal the identities of the men in the grotto. He attempts to kill Biscarrat and Biscarrat welcomes the murder, but the man dies before he can strike a fatal blow.
Distraught, Biscarrat throws away his sword and runs into the grotto crying that he is a dishonorable man and deserves to die.
The remaining men who follow are not so lucky. Only six men, including Biscarrat, remain after the gunfire.
Reinforcements arrive led by a captain. The survivors tell them the story and ask for help.
Biscarrat tells them that the men in the cavern are prepared to fight to the death unless the captain can offer them good terms.
The captain asks how many men there are.
When he learns that only two men are defending the grotto, he laughs.
Biscarrat asks if the captain remembers when four Musketeers held the bastion of St. Gervais against an entire army. The captain does remember, and Biscarrat tells him that two of those men are in the grotto.
All the soldiers are shocked to hear they are about to fight Porthos and Aramis, who are legends in the military.
Right now the death toll is ten, while the two defenders remain unscathed.
The captain readies his troops for battle.
Biscarrat makes one last plea for the men to be let go. The captain points out that he will look ridiculous if he orders the retreat of eighty men in the face of two.
He prepares to enter the grotto.
Biscarrat begs permission to be part of the first group to enter the grotto.
Biscarrat refuses to take his sword. He enters only to be killed.