While they are preparing to do the Robert Fischer job, Ariadne spots Dom Cobb in the middle of a dream, and she decides to join him by covertly sneaking in. She finds Dom and Mal Cobb talking, and Mal is immediately incensed that Ariadne is there and becomes aggravated and upset. Then, Cobb and Ariadne take a tour through the levels of Cobb's subconscious, and eventually, Ariadne finds herself in the basement, which is a destroyed hotel room that Mal is seemingly trapped in.
It's revealed that Cobb is locking Mal in the depths of his subconscious, but it's not clear why he is keeping her there or why she is so aggressive whenever she sees Ariadne. Later in the movie, we learn that the hotel room was the scene of Mal's death. She died by suicide in the presence of Cobb, thinking she was in a dream and not realizing she was in reality.
Her death constantly tortures Cobb, and he keeps her alive in his dreams through his memory of her. However, his practice of just keeping her locked in the basement of his mind is not working, and she is constantly breaking through — a sign that Cobb is trying to emotionally let go of her but just can't.
If you or anyone you know is having suicidal thoughts, please call the National Suicide Prevention Lifeline by dialing 988 or by calling 1-800-273-TALK (8255).
