Montag and Faber had hatched a primitive plan to subtly start a revolution in the minds of society by encouraging them to think for themselves again, to question what was happening around them. That plan was to start with Faber coaching Montag at his own home, with his wife and her two friends, by nudging them in the right direction.
But Montag moves too quickly, does too much too fast and reads them a poem while they are in the TV room, a poem so beautiful it makes one of the women cry. Both of his wife Millie's friends turn Montag in to Captain Beatty, but in the end, because she knows he has secretly hidden books and because of her own fear, Millie reports him as well. Montag has to lose everything in order to be free.
The three people that turned the alarm in against Montag were Mrs. Phelps, Mrs. Bowles, and Mildred.