Helen, an actress, approaches a Central London hotel. Inside a writer, Martin Ellis, waits nervously for her. At reception, Helen is approached by a businessman, who has mistaken her for an escort from the Moonlight agency. He is persistent, but eventually an outraged Helen manages to get him to back off.
At that moment, Martin enters the lobby in time to see the arrival of another woman, identical to Helen except for her shorter, strawberry blonde hair. The woman, Carol, greets Martin, assuming that he is the client who ordered her from the escort agency, until the nearby businessman intervenes and takes her away.
Helen sees Martin and greets him. He offers to take her bags up to his room before they head to the bar. On the way to the room Helen asks if it's true that Martin hasn't left his house for a year, which annoys Martin as he feels his agent, Ben (who has brokered the meeting), has been indiscreet. In his room Martin's lack of talent for small talk leads to a strained atmosphere. They discuss the reason Helen is here: Martin is blocked but has an idea that he wants to discuss with her that might release the block. Ben also implied to her that there might be a part in the eventual play for her. The two of them leave the room to go to the bar.
In the bar Martin explains that he has arranged the meeting because he wants to replicate the tension of a meeting between a man and woman that will form the basis of the play. Martin then goes on to express his issues with actors, particularly female actors, and presses Helen on the subject of how far she will go in order to get a part. Martin backs off and, as he goes to get a drink, spies the businessman and Carol across the room.
Returning to Helen, Martin quizzes her about a role she played in a sexually suggestive advertisement, but is distracted by the businessman and Carol. They disturb him because the planned subject matter of the play is the relationship between client and escort. As Martin stares across, the businessman is getting increasingly hot under the collar and some of Carol's comments to him closely resemble those of Helen to Martin.
Martin enters a reverie, remembering a scene from a television play in which Helen plays a young Catholic girl involved in an explicit sex scene. He pointedly explains to Helen that his own play climaxes with the client killing the escort, thus exploring the limits of what she would do in pursuit of her chosen profession. As he talks they are interrupted by a tannoy calling Martin to the phone.
When Martin returns Carol is preparing a note so she can make her escape. At that moment Ben, the agent, arrives and Martin rushes out again. Ben tells Helen that Martin has fallen in love with her, and she is disgusted.
Meanwhile the businessman and Carol agree a price for him to have sex with her, but despite this he gets visibly angrier during their exchange. Back in the bar, the atmosphere is tense and Ben leaves swiftly. Helen vents her annoyance at the sexism in the industry and by implication Martin before he goes on to ask her if she would be willing in the future to have sex in an acting role. This line of questioning finally becomes too much for Helen and she asks to get her things from Martin's room.
Up in another room, Carol demands her money and, after unsuccessful sex, the businessman attacks her. Martin and Helen are next door and as he hears Carol being attacked he grabs Helen in order to quieten her so he can listen. When he eventually turns to Helen he is horrified to see that he has killed her.
Martin is disturbed by a knock on the door. It is the businessman, who is married and entirely unlike his previous persona. Martin dismisses him and makes a phone call, perhaps to an escort agency, before lying on the bed next to the lifeless Helen and listening to the radio while smoking a cigarette.
