Tom Bates reluctantly invites a young man home to dinner. He mistakenly believes he is his disabled daughter's old school friend. Mrs. Bates nds their visitor, Martin Taylor, quite charming and welcomes the change in the long and arduous work of taking care of their seriously disabled daughter so she invites him to stay for a few days. Mr. Bates is quite wary of Martin, but in the interest of keeping peace with his wife, he agrees to let him stay. Martin slowly exploits the Bates' trust as he hatches an evil plot that will change all of their lives.