At the Bellero manor, a laser beam shoots out into the sky from the laboratory of Richard Bellero Jr. His father Richard Sr. looks on. Meanwhile, Richard's wife Judith sees her servant, Mrs. Dame, lurking barefoot in the shadows. They go down to the wine cellar and Judith has Mrs. Dame select a bottle of wine. Satisfied, Judith goes back upstairs to the laboratory and Mrs. Dame follows.
In the laboratory, Richard Sr. excuses himself and tells his son to pass on his appreciation of the dinner. When Richard suggests that Judith would like to hear it from Richard Sr., he doesn't respond. Judith returns with the wine, offering it to Richard Sr., he leaves. Richard tells his wife that Richard Sr. is passing over him as the CEO of the Bellero company. The scientist says that it has nothing to do with blood. Once Richard goes after his father, Judith throws the bottle across the room. She looks at the laser pistol that Richard has created, then sets it back and picks up the bottle. She looks up at the larger laser projector, and Richard returns and says his father has already left. He admits that his father wasn't impressed by his projector, since it's merely existing technology that he's found a new use for. Richard Sr. said that the corporation is no longer interested in destructive weapons, and Judith wonders if it is destructive. She says that she read of the legends of the Bifrost bridge, and thought the projector would be her bridge to greater holdings. Judith assures Richard that she loves him, and he wonders if that's enough to keep her. She kisses him for a moment and then asks him to return the wine until the next time Richard Sr. comes to dinner. However, after a moment Judith tells him to have Mrs. Dame bring two glasses so that they can share a toast.
Once she's alone, Judith breaks up the laser pistol and fires it, disintegrating the bottle. As she stares at it, the projector beam latches onto something and pulls it down out of outer space. It's a pale white humanoid alien, trapped in the beam. Horrified, Judith shoots at it and crawls out the door.
In the kitchen, Mrs. Dame is polishing the glasses. Richard asks if Judith ever confides to her about Richard, and he wonders if Judith has ever dreamed of needing him. Mrs. Dame insists that Judith is loyal, and Richard wonders to who. Judith stumbles in and said that she killed the newcomer, and they all go back to the lab. The alien is there, unharmed and surrounded by a transparent field. It says that they have heard of Earth and the fear of its inhabitants. The alien believes that it is wiser to be shielded until it has acquainted itself with all of their weapons. Judith wonders who the alien it, and it says that it comes from a realm that is an amplification of light. Using a device attached to its hand, the alien drops the shield and says that it uses it to travel into non-serene universes. It offers to go, seeing that they distrust it, and Judith apologizes for her actions. She says that she accepts the alien in her limited fashion and withdraws with Mrs. Dame.
The alien tells Richard that it will stay and asks about the laser projector. He says that it is similar to the composition of his world, and Richard explains as best he can. Judith listens from the hallway and then walks away, realizing that it is her bridge to the heavens. Mrs. Dames says that the alien is a creature that can't be killed, but Judith insists that it is alive... and theirs.
Later, Richard Sr. returns. He hesitates and then goes to the door. Mrs. Dame finally answers the door and Richard Sr. says that he came to see his son. She says that she was sent to send Richard Sr. away, but he takes offense and demands to see Richard. Judith arrives and dismisses Mrs. Dame, and lets Richard Sr. in. He admits that he's never approved of her and has done his best to keep Richard from regretting his marriage. Richard Sr. will let Richard have the corporation if he leaves Judith. Judith says that Richard wants his father's love, and she wants the Bellero empire. Disgusted, Richard Sr. says that her ambition is the greatest violence he knows of, and Judith says that he lusts for a heritage. She says that he will give his son the corporation in return for the great discovery he has made, and goes back inside. After a moment, Richard Sr. drives away.
Judith goes to the lab and finds the alien there with Richard. She quietly withdraws, and the alien tells Richard that it doesn't have much time. Richard goes after his wife and she realizes that he's genuinely happy for the first time. Mrs. Dame listens from the shadows as Richard says that he's been teaching the alien everything it can absorb, and it has lo leave in an hour. Judith dismisses her husband as a fool, pointing out that they will have no evidence the alien ever existed. She says that he owns the alien, and such accidents have made men kings. Judith hugs him and tells him not to lose the opportunity. Richard realizes that people wouldn't doubt his father if he testified that he saw the alien. Judith says that Richard should call him because Richard Sr. hates her, and Richard warns that the alien might resent being exploited.
Once Richard goes to the phone, Mrs. Dame emerges from the shadows and gives a gun to Judith. She explains that it once protected her from a human monster--her husband--and Judith may need the same protection. Judith takes it and enters the lab, and the alien recreates its shield. It analyzes her eyes and wonders why she wants it to remain, and Judith asks it to stay. She wants it to stay for Richard's sake, and assures the alien that she wouldn't harm it for the world. The alien lowers the shield and asks if it will come out of her shield. Judith looks at the device, and the alien says that she lacks the prime ingredient to use the object. It tells her that it is not a weapon but an anti-weapon, and a single one could protect the entire planet. However, it would do no good unless he or one of his people were there.
Richard returns and says that his father refuses to ever come back. She tells him to beg Richard Sr. to come, or she will crawl to get him there before it's too late. Richard agrees to do it rather than see her crawl, and begs the alien to stay. Once Richard leaves, the alien says that it did not promise to stay and if it misses the moment then it will never leave. Judith says that none of them can afford to miss the moment, and shoots the alien.
Judith and Mrs. Dame take the alien's body to the wine cellar. They hide it there temporarily until later when Mrs. Dame can dig a hole in the woods. Hey hear the door open downstairs and go up, and hear Richard Sr. talking to his son. Judith goes the rest of the way and thanks Richard Sr. for coming.
Richard goes to the lab and discovers that the alien is gone, having apparently left. Judith comes in and says that it left so that Richard couldn't exploit it. Richard is relieved that he didn't tell his father about the alien, and suggests that they claim it was a ruse so that Judith would apologizes. He asks if she'll apologize, and Judith says that she'll talk to Richard Sr. and asks her husband to wait there until they come up together.
In the cellar, Mrs. Dame listens as Judith tells Richard Sr. that Richard can't bring his discovery down. Richard Sr. goes to his car, and Judith follows him. She says that Richard has created the ultimate protective device and can either give it to humanity anonymously, or as the leader of the Bellero empire. After a moment, Richard Sr. gesso back inside.
Judith goes to the cellar and pulls the device from the alien's hand. As she leaves, she's unaware that the alien's blood--the prime ingredient--is leaking from the connecting tube. In the lab, Judith gets a bit of the liquid on her hand and then tries to wipe it off. She then asks for the honor of explaining Richard's shield, the Bellero Shield. Judith then gives a gun to Richard Sr. and asks him to fire it at her point-black. When Richard objects, Judith calls Mrs. Dame in and takes the gun. Judith creates the shield and Judith fires. The bullet is unable to penetrate the shield, and Richard Sr. takes the laser gun and fires it. It is also unable to penetrate the shield, and Judith says that the man who invented the shield could save the world... and asks Richard Sr. if he wants that man to succeed him.
Richard Sr. goes to his son and apologizes for projecting his self-doubts onto him. He begs his forgiveness and asks him not to shut him out of his success. Richard yells at him to stop and runs out, and Judith says that Richard doesn't forgive easily. She agrees to convince Richard to forgive him, and Richard Sr. asks her to do so quickly because he will soon be retired due to his failing health. Mrs. Dame tells Judith to go to Richard Sr. and comfort him before she discards him. However, when Judith tries to use the device to lower the shield, nothing happens. The shield is equally impenetrable from the inside, and Judith is trapped with her air running out.
The shield is proof against any and all cutting implements that they can use. Richard is unable to bring the alien back, Richard Sr. asks to be released to get help, but Richard insists that it isn't hopeless. He doesn't want anyone to know that his wife is a thief, and says that there's no one who can come. Judith starts to tell Richard the truth, but Mrs. Dame tells her not to. Despite that, Judith bursts into hysterical laughter and says that the authorities will move heaven and earth to dig a murderess out. She admits that the alien didn't tell her how to remove the shield, and says that nothing can remove it. Richard and his father stare in horror as Judith says that she killed the alien prematurely and hid his body in the cellar. Richard Sr. goes to the cellar when he hears where the alien is.
Mrs. Dame slips away and goes to the cellar. She drags the alien to the stairs, and Richard Sr. arrives. She says that she's going to bury it, insisting that the police cannot have their proof. Richard Sr. says that it belongs to the world, and his son will give it to them. Furious, Mrs. Dame knocks him down the stairs and Richard Sr. falls, breaking his neck. He lands next to the alien... and it opens its eyes.
Judith begs Richard to let her out, insisting that she's sorry. As she asks for forgiveness and freedom, the alien staggers in with Mrs. Dame. It says that it can free Judith and goes to the shield. Using the liquid from the vein on its hand, it creates a hole in the shield, reaches through, and takes the device. The alien then reattaches the vein and lowers the shield, and then collapses dead before fading away. Mrs. Dame says that it asked the alien to help, and it wondered how it could not.
Richard goes to a sobbing Judith and offers his hand. She steps forward…z and stops. In Judith's mind, the shield is still there and nothing will ever remove it. She fumbles at the imaginary walls, the spot of the alien's blood glowing on her hand.