''Deadly Friend'' is a 1986 sci-fi/horror film directed by Creator/WesCraven, based on the novel ''Friend'' by Diana Henstell.

TeenGenius college professor Paul moves into a new neighborhood with his mom and [[RobotBuddy his sentient robot B.B.]] and soon meets GirlNextDoor Samantha (Creator/KristySwanson) and her [[AbusiveParents 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 [[CyberneticsEatYourSoul more robot than human]] and things go downhill from there.

!!Tropes present include:

* AbusiveParents: 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 AssholeVictim soon enough.
* AllJustADream: Some people's interpretation of [[GainaxEnding the crazy ending]].
* ArtificialZombie: Undead Sam.
* ArtisticLicenseBiology: It's highly unlikely that a computer chip could reanimate someone who is brain-dead. [[spoiler: Even more unlikely is that computer chip changing a person's bones into a robotic skeleton.]]
* AssholeVictim: Sam's dad, who for reasons above, deserved every single moment of his death.
** LaserGuidedKarma: His death came in the form of his resurrected daughter murdering him.
* CameBackWrong[=/=]CyberneticsEatYourSoul
* DisappearedDad: Paul's father is absent without any explanation.
* GainaxEnding: [[spoiler:Sam's insides turned into a more evil B.B....somehow]].
* GirlNextDoor: Sam.
* KillerRobot: B.B. was already starting to show homicidal impulses before his brain was inserted into Sam's.
* MadeOfPlasticine: How else do you explain someones [[YourHeadAsplode head exploding]] by getting hit by a basketball?
* MissingMom: Sam's mother, and according to Sam's dream her father might have murdered her.
* NinjaPirateZombieRobot: Undead Sam.
* OverprotectiveDad: Sam's is of the more deranged sort.
* PokemonSpeak: B.B. keeps repeating its name in its robot body.
* PoisonousFriend: B.B.
* RobotBuddy: B.B.
* RobotGirl: Sam after the transplant.
* SuperStrength: One of the side effects of Sam having a robotic brain.
* TeenGenius: Paul.