Beamish's sister is Nancy, the woman Harry met on the railroad tracks. She owns the house they want to make HQ for the secret army. Beamish calls it "Operation Charm" and gives Harry money to take her to dinner to get her on side. They also have to let her join the army if she says yes. Meanwhile, Harry assumes she will say yes and invites 3 recruits to the house for the weekend. Nancy realizes that he is not there for a visit, but is in her house to set up a secret army. After several dinners out, she gives in.
—Britstuff