some things for supper; one of the policemen goes to the store to speak with the grocer:

In fifteen minutes he was back with a page of notes, and there was more whispering, and through her sobbing she heard a few of the whispered phrases-”...acted quite normal...very cheerful...wanted to give him a good supper…peas...cheesecake...impossible that she...”

This presents the idea that Mary was under some suspicion at least as a technicality because the policeman goes to corroborate her story, and they assume they can dismiss her from a list of likely suspects.

There may also be some suspense when they search for the murder weapon. The reader knows how Patrick was killed. Even when Mary hit him, the narrator (using foreshadowing) notes:

She might just as well have hit him with a steel club.

The fact that the police remain at the house, searching for clues provides suspense in that until they are satisfied that there is nothing that might implicate Mary in the murder, Mary is not yet safe. As they search for the weapon, which the police note could have been taken by the murderer or hidden on the premises, the audience is left to wonder if Mary will be caught. The importance of the leg of lamb is evident as Jack Noonan explains the integral nature of the weapon to their investigation:

“It’s the old story,” he said.  “Get the weapon, and you’ve got the man.”

The last bit of suspense occurs when Noonan reminds Mary that the lamb is still cooking. She pretends to be startled and asks him to turn the oven off. There is never the slightest indication that Jack Noonan suspects anything about the once-frozen leg of meat now finished cooking. To bring the suspense to an end, Mary tearfully invites the men to eat dinner with her. When they agree and eat their fill, the police (of all people—how ironic) have unknowingly disposed of the evidence, and Mary's freedom is assured.

Mixed in with the suspense and irony is black humor, where the grotesque circumstances of Patrick's death provide not only suspense, but comedy as well, as the men eat the only thing to tie Mary to the crime. As they finish their meal, the men discuss the case:

“That’s the hell of a big club the gut must’ve used to hit poor Patrick,” one of them was saying [...] "Whoever done it, they’re not going to be carrying a thing like that around with them longer than they need.”

One of them belched.

"Personally, I think it’s right here on the premises.”

“Probably right under our very noses."

How right they are!

First of all, he shocks us when Mary knocks her husband over the head, killing him.  This is incredibly surprising, because she was such a docile, sweet, loving character; she didn't even react emotionally when her husband told her that he was leaving her.  She just calmly went downstairs to get something for dinner.  Then, out of nowhere, bam!  She nails him on the head.  That initial shock to the reader really sets the stage for the suspense to come.  We are jarred and left tense, wondering what she will do.  Then, she is STILL calm, and we are thinking to ourselves, "Why isn't she freaking out right now?  What is she planning?"  That is very suspenseful.

When she goes upstairs and practices smiling and talking in front of the mirror, that creates suspense because we have no idea what she is planning.  She is formulating some sort of scheme, but the author doesn't let us know what she is thinking, so we don't know what it is; this creates suspense.  We are on the edge of our seats as she goes to the grocer, lies to his face, plays it cool; her calmness alone creates suspense.

The author creates the most suspense when he has the cops come right to her house.  We are anxious that they will find out what has happened; we wait, tense, as the questions are asked, as they search the house.  Then, the final dose of suspense; Mary has the audacity to feed the officers the lamb.  They are entirely clueless, but we are worried the entire time that they will figure it out.

So, with an initial jarring shock at the murder, through leaving out her thoughts at key points, and through bringing the cops to the scene (and weapon) of the crime, Dahl creates suspense for the readers.

Actually, the reader is taken by surprise much as Patrick Maloney himself! There is no time to wonder how the murder will be committed since no one suspects anything. However, the reader is aware that Mrs Maloney feels betrayed and totally let down, and especially vulnerable given her maternal state. For this reason, her sudden brutal act can be justified, even if it is "out of character" with her character profile.

There is suspense, however, after the murder scene in that the reader follows Mrs Maloney around in her meticulous steps to cover her crime. One can wonder how such a sentimental and docile wife can show herself to be so calculating and cool-headed. When the police arrive, the reader waits for the moment which never comes - the moment Mrs Maloney gets caught. There is an unfulfilled expectation.

Mrs Maloney's giggle at the end also takes the reader off guard. Not exactly the grieving widow, perhaps she is even enjoying " getting away with murder."

I think that one of the key ways in which Dahl creates tension in this darkly humorous and incredibly ironic short story is through the killing of Patrick Maloney by his wife, Mary. Mary is deliberately described in great detail as the ideal, loving and caring wife, who is completely devoted to her husband. Note how the text says:

She loved to luxuriate in the presence of this man, and to feel - almost as a sunbather feels the sun - that warm male glow that came out of him to her when they were alone together.

This is clearly rather over the top, but it also makes us feel incredibly sympathetic towards her when we discover her plight when Patrick tells her he is leaving her. Her murder of course is a shock - we don't expect a woman who is so devoted to her husband to suddenly kill him, but it also increases the tension incredibly by making us wonder what will happen to her and what her fate will be, especially as she is pregnant. It is this that, above all, raises the tension as we wait and see how Dahl resolves this deliciously wicked tale.

The setting of this wonderfully dark short story is the Maloney household. Other than her brief trip to the store, Mary Maloney stays within the confines of her home. That closeness helps maintain a suspenseful atmosphere. It is similar to the original Jaws movie or Alien movie. Both of those stories were limited to within the confines of a small ship/boat. There isn't any escape, so that helps build tension.

For "Lamb to the Slaughter," readers know that Mary killed Patrick, and she doesn't get rid of the body or murder weapon. Mary doesn't even attempt to run away. In fact, she returns to the scene of the crime and fully embraces her plan. Once it is in motion, she is fully committed to it. Like those movies, there is no escape for Mary other than the success of her plan.

Everything is on scene for the police to look at and look through. Mary Maloney is only ever one small step away from being caught. Serving the police the leg of lamb is an incredibly bold and tense move on her part. It is a smart move, but it is suspenseful nonetheless because the police are holding the murder weapon. It is quite literally right under their noses, and readers know it. That knowledge is suspenseful.

I will start with surprise. The story is loaded with surprises for the reader.  When the reader is introduced to Mary, she is the quintessential doting wife.  She is sitting at home eagerly awaiting the arrival of her husband.  When Patrick finally does get home, she rushes to welcome him, calls him "darling," and is eager to get him a drink and have him sit and relax.  The reader can only assume that Patrick's feelings for Mary are similar.  That's why it comes as quite a surprise that he tells Mary that he is leaving her or divorcing her.  It's also surprising to see that Mary, despite her meek introduction, kills Patrick with a single blow.  Mary keeps the surprises coming, because she doesn't panic and fall apart at her murderous deed.  Rather she collects herself and goes about setting an alibi in order to get away with the murder.  

Dahl foreshadows the murder and the murder weapon when he has Mary specifically mention the lamb in the freezer.  

"We can have lamb. Anything you want. Everything's in the freezer."

Mary is absolutely correct.  Everything she needed was in the freezer.  

There is irony in the title of the story.  Most readers likely assume that a "lamb to the slaughter" literally means a lamb being killed.  As a metaphor, the phrase is often used to describe a person being killed.  Jesus is often referred to in this manner.  But in this story, the lamb that is coming to the slaughter is a lamb that is actually doing the slaughtering.  The lamb kills Patrick.  It's totally unexpected.  

There is dramatic irony at the end of the story as well.  The reader knows what has happened, and knows that the murder weapon is literally right under the noses of the police investigators.  

"It's probably right under our noses. What do you think, Jack?"

That's because they are eating the murder weapon. Yum. 

This is a very good question. The story is told entirely from Mary Maloney's point of view. The reader identifies with her because we are held in her point of view from beginning to end. Early in the story we understand her emotions. She is in love, she feels content, and she is six months pregnant. We wish her well. After she commits her murder she has to call the police. Since we are held in her point of view, we cannot know what the police are going to do or what they are going to think. When she goes to the grocery store to establish an alibi, she is still improvising. She knows she has to go back home and pretend to find her husband's body, then call the police and pretend to be in panic and shock, and then to put on an act of innocence and mourning while police swarm all over her house and one or two of them ask her questions. She doesn't know what kinds of questions they might ask. She doesn't know what they might suspect--or even what they might know about Patrick that she doesn't know.

It is because we are held in her point of view that we share her suspense. She is trying to get by with murder, but she doesn't know whether or not she is going to succeed. She knows that it is very hard to get by with murder, and she knows that spouses are often prime suspects. She has to keep her cool. She has never played this role before. That is why so many murderers get caught. They overact. They don't know how to play the part. Mary knows she must be bereaved but not too bereaved. How do women act when their husbands are murdered? Maybe they simply act as if they are in a state of shock and do not show much emotion?

It is a very nice touch that Mary wants to go on about her daily routine, which at this time of day involves cooking a leg of lamb. It seems natural for some people to be in a state of denial and to want life to go on just as it had been going on before. She could play that role rather than acting as if she were totally overwhelmed and incapacitated. After all, she is a cop's wife. She knows her husband faces danger every day. He would expect her to be tough. These cops who have invaded her home are all Patrick's buddies. She would be expected to show them some hospitality in spite of her suffering. She is never entirely safe. She never knows what is going to happen next. In making the radical decision to murder her husband, she was entering into a strange new world.

A parallel example is Rodion Raskolnikov in Fyodor Dostoevsky's novel Crime and Punishment. He intends to murder one woman. Another woman shows up unexpectedly and he has to murder her too. Then he can't get out of the murdered women's apartment because a group of people has collected outside in the hallway. When he does manage to get away, he has to worry about the police investigation. He is under a strain throughout the novel, and the reader, held in Raskolnikov's point of view, suffers the strain along with him.

Setting

The setting facilitates tension because of the enormous detail in how very perfectly peaceful it is. Mary sits alone at home, watching the clock but "without anxiety." The simple inclusion of these words heightens our own sense that something is amiss. The immediate thought becomes Should she be anxious? She watches the clock because every minute that passes brings her husband closer to returning from work.

She is "curiously peaceful" as she waits, with the adverb indicating that there is something unusual about her ease. Of course, this is a time period when Mary is living the very role that society expects of her, and her actions reflect her deep need to make her husband as comfortable as possible at every turn. When she jumps to refill his drink and is commanded to sit down, the tension in their home becomes clear.

Dialogue

One example of this is found in the lack of dialogue provided as Patrick conveys his reasoning for leaving his six-months-pregnant wife. In that omission, the reader is left much as Mary must have felt: confused and without answers. It's a blur that creates tension reflected in Mary's next verbal response: "I'll fix some supper." Clearly she cannot process this information and is blindsided by her husband's betrayal, and the reader is left knowing that her dinner will never happen—yet not knowing at this point how or why.

Later, Mary mentions the leg of lamb directly to the grocer, bringing her murder weapon right into casual conversation. This move furthers the tension by showing Mary's boldness in inventing an alibi. And then when she returns home, she calls out to the husband whom she knows is dead in an effort to make herself believe her own alibi.

Imagery

The murder itself has imagery which furthers the tension:

The violence of the crash, the noise, the small table , helped to bring her out of the shock. She came out slowly, feeling cold and surprised, and she stood for a few minutes, looking at the body, still holding the piece of meat tightly with both hands.

The tension is high here, with the reader wondering if "the body" really means that she has killed her husband. The next line makes this clear. This scene is followed with the eerily ordinary household imagery of a wife preparing a dinner she won't need:

She carried the meat into the kitchen, put it into a pan, turned on the oven, and put the pan inside. Then she washed her hands, ran upstairs, sat down in front of the mirror, fixed her makeup, and tried to smile.

Her calmness is surreal, furthering the tension regarding how her crime will be seen and what punishment will befall Mary.