- Act Three finds us at the apartment of Henry Higgins's mum. Higgins, it seems, wants to test his work at a party she'll soon be throwing.
- Mrs. Higgins does not approve of the idea – you get the feeling she doesn't approve of most things Higgins does – but Higgins doesn't listen. He's not one to take no for an answer. He's also, we find out, not interested in women, really. Except women like his dear old mother.
- Higgins assures his mother that Eliza will be on her best behavior, and talk only about the weather and other people's health.
- Turns out the whole thing isn't much of a party. The only guests are the mother and sister from the first act, Mrs. and Miss Eynsford Hill, good old Freddy, Pickering, and, of course, Eliza.
- Eliza enters the party last, looking stunning, and proceeds to ask everyone "How do you do?" She acts a bit like a robot – a beautiful robot with a perfect accent and a very small vocabulary.
- Higgins spends most of the time trying to figure out why the Eynsford Hills look so familiar.
- By the time he figures it out, Eliza has forgotten to stick to the script. She starts talking about how her aunt was "did in" by someone. Freddy, not the sharpest tool in the shed, is laughing like an idiot. His vocabulary seems pretty small too (e.g., "Ha! Ha! How awfully funny!" and "Killing!" He thinks Eliza's a comedian, not a Cockney girl). Higgins, embarrassed, gives the signal – a cough – and Eliza heads off like clockwork.
- After the Eynsford Hills leave, Mrs. Higgins gives Henry and Pickering a talking to. She scolds them like they're little boys.
- They assure her that they're treating Eliza well, not like a doll at all, but Mrs. Higgins doesn't buy it. Things start to get heavy, and we're not exactly sure why.
- You idiots, she says, if Eliza learns to act like a lady, she won't be able to do anything to make a living!
- Higgins and Pickering skip away, unconcerned.