Strong allusions to domestic violence. The main character sees his mother with a black eye and is told that she was given it by her live-in "boyfriend"; the same man later threatens the son with a knife.
Much other violence and extended fight scenes, some stylized, but much of it very realistic. For example, during an early scene, a man's body is sliced in two parts by a sharp blade.
A tooth is knocked out of a man's mouth during a brawl and the camera follows it through the air in slow-motion.
A massacre takes place in a church, that includes extremely violent methods of murder. Dozens of people are brutally killed during this scene, with shootings, stabbings, impalement, and other painful ways to die occurring. The scene is like a zombie movie scene but the victims are not zombies, but people. Throughout the scene background characters fight to the death as one of the main characters (a good guy) murders many people, all of whom are civilians. The audience is expected to root for his survival but the good guy is shot in the head at the end of the scene. This possibly the most graphic and bloodiest scene in the film.
In a highly stylized scene, many people have their heads explode in detail, yet there is hardly any blood. The head explosions are colored, mostly orange and purple animated mushroom clouds (a scene evocative of Dr. Strangelove). Many of these people are world leaders, including a fictional version of President Obama.
A villain sends a signal through cell phones which is intended to make people become violent and aggressive. As his plan appears to be working, scenes of massive brawls are shown in several major world cities, with car crashes, fires, etc. The villain gloats over these scenes with glee.
One scene has an antagonist slicing off the hand of a good guy using her prosthetic legs. Very violent, although stylized and not seen in detail.
Two scenes in this film contain graphic head explosions, unlike the animated mushroom clouds. One scene contains a scientist getting his head blown up with some blood/viscera shown.
The other scene contains a secondary antagonist suffering the effects of Valentine's head exploding chip , in which his eyes dramatically bulge up before his head pops like a balloon, some blood and viscera shown.
One extremely intense scene that occurs when Valentine's SIM card causes everyone to go feral in which a mother, suffering the effects of the SIM card , attempts to attack her child with a butcher knife. Prior to this scene, the main protagonist tells her to lock the child in the bathroom, and the mother attempts to break through the door with the knife. VERY intense and disturbing.
Towards the end, after Eggsy defeats Valentine, Valentine , proceeds to puke, because "He can't stand the sight of blood"
One scene has the main protagonist almost getting run over by a train.