Deadly Friend is a 1986 sci-fi/horror film directed by Wes Craven, based on the novel Friend by Diana Henstell.
Teen Genius college professor Paul (Matthew Labyorteaux) moves into a new neighborhood with his mom and his sentient robot B.B. and soon meets Girl Next Door Samantha (Kristy Swanson) and her abusive father. Things start out great and the kids have a good time, but it's not long before a series of tragedies occur: B.B. is destroyed by the paranoid elderly neighbor lady after they pull a prank on her; Samantha is killed by her father in a drunken rage; Paul decides to bring Samantha back to life by use of a brain transplant using B.B.'s computer chip brain, but the transplant makes her more robot than human and things go downhill from there.
Tropes present include:
- Abusive Parents: Sam's dad is of the physical sort and, according to her dream, he may also have sexually abused her. He gets extreme when he kills her. He becomes an Asshole Victim soon enough.
- All Just a Dream: Some people's interpretation of the crazy ending.
- Artificial Zombie: Undead Sam.
- Artistic License – Biology: It's highly unlikely that a computer chip could reanimate someone who is brain-dead. Even more unlikely is that computer chip changing a person's bones into a robotic skeleton.
- Asshole Victim: Sam's dad, who for reasons above, deserved every single moment of his death. Also, few mourned Elvira or Carl.
- Laser-Guided Karma: His death came in the form of his resurrected daughter murdering him.
- Came Back Wrong/Cybernetics Eat Your Soul: Sam (and B.B.) being brought back to life courtesy of B.B.'s brain chip leaves her a very brain-damaged girl that can't talk up until the end when she screams out "Paul!" before being shot by the police except for making beeping muttering noises like B.B., needs to be led around and taught things again, and whose only desires left in mind are to get bloody revenge on the people who hurt her and Paul.
- Disappeared Dad: Paul's father is absent without any explanation.
- Evil Old Folks: Elvira Parker, the paranoid and vile old woman of a neighbor. The movie's turn to tragedy and horror begins when she destroys B.B.
- Fun-Hating Confiscating Adult: Elvira Parker's Kick the Dog act that happens one scene before the Halloween sequence and her blowing BB away with a shotgun is her taking the teens' basketball that had landed on her porch. The teens' decision to get back at her for this in Halloween is what ends up causing all of the horror of the rest of the film.Tom "Slime" Toomey: Hey, you can't do that!
Elvira Parker: Yes, I can. My property, my house... (pause, smug little smile appears on her face) my ball. (tosses ball inside house, walks in, closes the door) - Gainax Ending: Sam's insides turned into a more evil B.B.... somehow.
- Girl Next Door: Sam.
- Hair-Trigger Temper: Both Elvira Parker and Sam's dad. All of the tragedy that turns the film into a horror story happens because they get murderously enraged on the protagonists.
- Improbable Weapon User: A basketball in a robot girl's hands becomes a deadly weapon.
- Kick the Dog: Elvira Parker's destruction of B.B. has her shooting B.B. with a double-barreled 12-gauge shotgun (that blows off one of the robot's arms and has it screaming in apparent pain, which would probably be enough damage to deliver the message to any onlookers to never get in her garden again), calmly reloading her gun, and then tearing B.B. apart with both barrels before turning to a grieving Paul (and the other teens that were hiding on some bushes nearby) and giving them a smug smile.
- Killer Robot: B.B. was already starting to show homicidal impulses before his brain was inserted into Sam's.
- Made of Plasticine: How else do you explain someones head exploding by getting hit by a basketball?
- Missing Mom: Sam's mother, and according to Sam's dream her father might have murdered her.
- Ninja Pirate Zombie Robot: Undead Sam.
- Offing the Offspring: Sam's abusive dad killing her in a drunken rage kickstarts the plot.
- Pokémon Speak: B.B. keeps repeating its name in its robot body.
- Roaring Rampage of Revenge: The ressurected Sam/B.B. wants to get back at those who hurt her/it and Paul. And it will not stop.
- Robot Buddy: B.B.
- Robot Girl: Sam after the transplant.
- Super-Strength: One of the side effects of Sam having a robotic brain.
- Teen Genius: Paul. He moves to the town the film takes place in to teach at the local school and developed a fully sentient robot.
- Toxic Friend Influence:
- B.B. It starts developing an "evil mode" shortly before it's destroyed and once Sam gets its brain chip, she becomes a psychotic murderer.
- Sam's and Paul's friend Tom — everything bad that happens occurs because he decided it was a good idea to dare them to pull a ding-gong-ditch on the crazy old woman that had turned her home into a fortress and threatens to shoot anybody who so much as looks at her funny or stands in front of her house for too long.
