For a three-act plot analysis, put on your screenwriter’s hat. Moviemakers know the formula well: at the end of Act One, the main character is drawn in completely to a conflict. During Act Two, she is farthest away from her goals. At the end of Act Three, the story is resolved.
Act I
We meet Mrs. Freeman and her three facial expressions, Mrs. Hopewell and her platitudes, Hulga and her Ph.D, and Manley Pointer and his Bibles.
Act II
Hulga forgets to bring food to the picnic, but Manley is totally prepared—his hollowed out Bible comes complete with whiskey, cards, and condoms. But Manley shows Hulga his party favors after he has her leg and is refusing to give it back. So, naturally, she's not impressed. We don't know how she would have reacted if she'd had her leg on when he reveals his secrets, though we do know she at least planned to have sex with him.
Act III
After he steals Hulga's leg, Manley is seen leaving by Mrs. Hopewell and Mrs. Freeman, who are digging up onions. Mrs. Hopewell definitely has no idea he's been with Hulga, but Mrs. Freeman might or might not have her suspicions. In any case, we don't see Manley or Hulga again.