The Giant's Wife (or The Giant) is the true main antagonist from the 2014 Disney film Into the Woods. She is played by Frances De La Tour.
Into the Woods
The Giantess was mentioned by Jack when he journeyed into the castle of her husband, the male Giant, where she kept Jack hidden from him. After her husband dies from falling down Jack's beanstalk, she enters the woods below intending to get vengeance against the boy. She appears in the woods demanding where Jack was to the group of people, killing Jack's mother in the process. To stop her rampage, the Baker, Jack, Cinderella and Red Riding Hood fake Jack's death to the Giant while she gets hit by the Baker and Jack and falls over, resulting in her death.
Trivia
She is from the original tale "Jack and the Beanstalk" as the wife of the Giant. However, this version is based more closely on the one from the original musical of Into the Woods.
The Giant was the only giant alive after her husband died.
The Witch was introduced as the main antagonist of the film, but the Giant winds up taking that role because she is more evil and had bigger plans than the Witch.