I am a movie director and I just received the following movie plot. Could you help me answer this question? If not, let me know by writing "Not answerable". Plot title: Let Me In Movie plot: March 1983. Los Alamos, New Mexico. A group of police cars, with sirens wailing, escort an ambulance to Los Alamos Memorial Hospital. They are carrying an unidentified 50-year old man with acid burns to the face. He is placed on a respirator because the toxic fumes from the acid have seared his lungs and thus compromised his ability to breathe. A Detective (Elias Koteas) attempts to speak with him, asking him to identify himself and wondering whether he is a part of a Satanic cult. He gets no reply. A nurse calls him to the front desk to take a telephone call from the receptionist in the lobby who reports that the man's daughter is asking about him. Hearing a sudden change in the beeping of his respirator, the nurse returns to the man's room and screams. The man has jumped out of his tenth floor window to his death, leaving only a note that reads: "I'm sory [sic] Abby".Two weeks earlier. Twelve-year-old Owen (Kodi Smit-McPhee) is sitting alone in the snow-covered courtyard of his apartment building, singing to himself, until his mother (Cara Buono) calls him for dinner. Owen's parents are in the process of a nasty divorce, and Owen is often left to eat alone and amuse himself by playing alone in his room. One evening, he notices a girl (Chloe Grace Moretz) about his age and her father (Richard Jenkins) moving into the apartment next door to his. Oddly, she is wearing no shoes.The next day at school, Owen is picked on as usual by three older boys -- Kenny (Dylan Minnette) and his friends Mark (Jimmy 'Jax' Pinchak) and Donald (Nicolai Dorian). Out of fear, wimpy Owen doesn't fight back, even though they give him a wedgie, causing him to urinate on himself. That evening, as he sits in the courtyard rehearsing knife attacks on his tormentors, he notices the new girl, Abby, watching him. She's not very friendly and tells him right off that they can't be friends. Not long afterwards, her father walks through the courtyard. It is revealed to the viewers, and what Owen doesn't know, is that he is not Abby's... My question: How does Abby and Owen communicate?
The answer to this question is:
Through Morse code, tapping on the wall that separates their apartments