A police lieutenant uncovers more than he bargained for as his investigation of a series of murders, which have all the hallmarks of the deceased 'Gemini' serial killer, lead him to question the patients of a psychiatric ward.

Patient X: I have dreams... of a rose, and then of falling down a long flight of steps.
Dt. Kinderman: This I believe in... I believe in death. I believe in disease. I believe in injustice and inhumanity, torture and anger and hate... I believe in murder. I believe in pain. I believe in cruelty and infidelity. I believe in slime and stink and every crawling, putrid thing... every possible ugliness and corruption, you son of a bitch. I believe... in you.
The Gemini Killer: I like plays. The good ones... Shakespeare... I like Titus Andronicus the best; it's sweet. Incidentally, did you know that you are talking to an artist? I sometimes do special things to my victims: things that are creative. Of course, it takes knowledge, pride in your work... For example, a decapitated head can continue to see for approximately twenty seconds. So when I have one that's gawking, I always hold it up so that it can see its body. It's a little extra I throw in for no added charge. I must admit it makes me chuckle every time. Life is fun. It's a wonderfull life, in fact... for some.
The Gemini Killer: Well, there I was so awfully dead in that electric chair. I didn't like it. Would you? It's upsetting. There was still so much killing to do, and there I was, in the void, without a body. But then along came - well - my friend. You know. One of them. Those others over there. The cruel ones... the Master. He thought my work should continue. But in this body. This body in particular, in fact. Let's call it revenge. A certain matter of an exorcism, I think, in which your friend Father Karras expelled certain parties from the body of a child. Certain parties were not pleased, to say the least. The very least. And so, my friend, the Master, he devised this petty scheme as a way of getting back, of creating a stumbling block, a scandal, a horror to the eyes of all men seeking faith, using the body of this saintly priest as an instrument of, well, you know - my work. But the main thing is the torment of your friend Father Karras as he watches while I rip and cut and mutilate the innocent, his friends, and again, and again, on and on! He's inside with us! He'll never get away! His pain won't end!
[Abruptly calm and composed]
The Gemini Killer: Gracious me. Was I raving? Please forgive me. I'm mad.
Kanavan: Try and make a good confession, and remember, Christ forgives all our sins.
Penitent: Only little things. Nothing. Seventeen of them, Father. The first was that waitress in Candlestick Park. I cut her throat and watched her bleed. She bled a great deal. It's a problem I'm working on, Father. All this bleeding.
The Gemini Killer: It's too bad about Father Dyer. I killed him, you know. An interesting problem, but finally... it worked! First, a bit of the ole succinylcholine to permit one to work without, ah, annoying distractions, then... a three foot catheter threaded directly into the inferior vena cava - or, superior vena cava. It's a matter of taste, I think, don't you? Then the tube moves through the vein, under the crease of the arm, into the vein that leads directly into the heart, and then, you just hold up the legs and you SQUEEZE the blood manually into the tube from the arms and the legs. There's a little shaking and pounding at the end for the dregs - it isn't perfect, there's a little blood left I'm afraid. BUT, regardless, the overall effect is astonishing! And isn't that REALLY what counts in the end? Yes, of course, GOOD SHOW BIZ, Lieutenant, the EFFECT! And then, off comes the head without spilling one single drop of blood. Now I call that SHOWMANSHIP, Lieutenant!
The Gemini Killer: It's the smiles that keep us going. The bits of giggles and good cheer.
Patient X: You again. You've interrupted me. Well... come in, Father Morning. Enter, knight. This time you're going to lose.
Patient X: I kill at random... no motive... that's the fun.
Patient X: I still hear from her occasionally, screaming. I think the dead should shut up, unless there's something to say.
Dt. Kinderman: My wife's mother is visiting, Father. And Tuesday night, she's cooking us a carp. It's a tasty fish, I've got nothing against it. But, because it's supposedly filled with impurities, she buys it live and for three days, it's been swimming... up and down... in my bathtub. Up and down... and I hate it. I can't stand the sight of it, moving its gills. Now, you're standing very close to me, Father; have you noticed? Yes. I haven't had a bath for three days. I can't go home until the carp is asleep because if I see it, swimming... I'll kill it.
Father Paul Morning: [performing exorcism] You robber of life! You author of pain! You corruptor of justice, and innocence, and youth!
Father Dyer: [in a hospital complaining that he's read all of the newspapers already] Now look, these are all last weeks editions. I've read every one of them. No, can't ya pick me something up?
Dt. Kinderman: My god, the grammar.
Patient X: Death, be not proud, though some have called thee mighty and dreadful, for thou art not so; For those who think'st thou dost overthrow die not, poor death, nor yet canst thou kill me.
The Gemini Killer: Catatonics are so easy to possess...
Father Dyer: May the schwartz be with you.
Patient X: [flashback from 'The Exorcist'] Take Me. Come into Me!
Patient X: Incidently, who is this Damien you mentioned?
Dt. Kinderman: Don't you know him?
Patient X: I know nothing! Except I must go on killing Daddy! I must shame him!
Father Dyer: I only told him the truth.
Stedman: What did you say?
Father Dyer: Jesus loves you, everyone else thinks your an asshole.
Dt. Kinderman: Are you Damien Karras?
Patient X: Aahh, you haven't any medical records for him, have you? No tedious fingerprints?
Dt. Kinderman: That's commendable.
Father Dyer: (On the film 'It's a Wonderful Life') I've seen it 37 times.
Patient X: [Damien Karras is unpossessed] Now free me...
Mrs. Clelia: My radio. Aren't you going to fix it? Nothing ever gets fixed round here. Just a whole bunch of pies and anchovies. Go away. I don't ever talk to strangers.
Dt. Kinderman: I'm the radio repairman, Mrs Clelia.
Mrs. Clelia: Well then, fix it.
Dt. Kinderman: What's wrong with it?
Mrs. Clelia: Dead people talking. It's right here. Do you see it?
Dt. Kinderman: Yes. I see it.
Mrs. Clelia: I just knew you weren't really a radio repairman. That's a telephone I'm holding.