The title is an appropriate play on "a guest in the house."
A labor shortage "became so bad" that employers are compelled to hire "anybody or anything". Daffy is a hotel bellboy and Elmer is the manager in the Gland Hotel. A tired man demands peace and quiet, and threatens violence against Elmer if disturbed. "Just one more thing. I'm a tired man. I gotta have my sleep, plenty of it. So see to it that I get lots of peace and quiet. Because if I'm disturbed at any time, I'm gonna bust you right in the nose!" Daffy, Jerry Colonna-like, remarks: "Likable chap, isn't he!" Daffy does many stunts that keep the man awake, complete with escorting him to room 666. Every time he is awakened again, the increasingly-irritated man trudges to Elmer's station, to the tune of "Pop Goes the Weasel", and at the moment where the song would say "pop", he busts Elmer in the face.
- Daffy pounds a "Do Not Disturb" sign on the door and wakes the exhausted man up, and when the man opens the door, Daffy accidentally pounds his face.
- Daffy opens a window which releases a loud gail which frightens the man to the ceiling, and when the man comes down, closes it and returns to his sleep, and Daffy leaves the room, a drunken man in the other room sings "How Dry I Am". Just when he was going to beat the drunk, Daffy says that he'll "muzzle that inebriated canary", only for the naive duck to get drunk and sing along.
- Daffy is singing and cleaning a window and finds a small speck and the scratching wakes and irritates the man. He calls Elmer by telephone and punches him through the phone!
- Daffy hears a funny story about a Salesman trying to sell something to a farmer when the farmer doesn't want it and wakes the man to tell the story and the man nonchalantly walks down to Elmer, who is protecting himself with a knight's helmet only for the man to punch him. Then, Daffy doesn't even remember how his joke ends, but still laughs, and then Elmer comes in and shushes Daffy to be quiet, only for the manager to be beaten.
When Daffy says it is too cold, he decides to fix the radiator. Elmer, fearing getting beat up again, chases after Daffy. Daffy makes the heat vibrate to the room. Elmer, fearing that the room might Explode along with the man, hears whistling and covers it with several pillows. Daffy, thinking that Elmer is blowing whistles and trying to kill the man, rants to him by saying "So, a fine kettle of fish! Here I work myself down to the skin and bones trying to keep this guy asleep and what do you do? Blow whistles! Just when I got things so quiet you can hear a pin drop, you bust in here and bust out with a whistle and you snafu the whole works! How in the name of all things reasonable do you expect a guy to get his slumber when a goof like you goes around making noises like a one-man 4th of July celebration?! He needs peace and quiet! It's positively outrageous!" Elmer nervously tries to shush Daffy but Daffy's screaming obviously wakes the now enraged man who shows red swirls in his eyes and grits his teeth, so Elmer hurries downstairs and he and Daffy switch places in an effort to fool the man, but Elmer gets beat up anyway. Daffy, again like Jerry Colonna says, "Noisy little character, isn't he!"
- The version that aired on Kids' WB! edited out the part where the man is kept awake by a drunk man in the next room singing "How Dry I Am" and Daffy tells the man that he'll "muzzle that inebriated canary" only to drink up with the drunk man and sing along in harmony.
- Towards the end of the cartoon, when Elmer rings for Daffy and Daffy runs up to the front desk and says, "Yes, sir!", his lips don't move.
- When Daffy sings "Time Waits for No One" while cleaning the window, his lips don't move when he sings the last line of the song.
- The film is notable for featuring a sort of "in-between" interpretation of Daffy. He is not necessarily the zany, impish interpretation used famously by Tex Avery and Bob Clampett, nor is he the greedy, self-centered version that Chuck Jones later popularized in the 1950s. As Paul Dini said in the DVD audio commentary for this cartoon, "[In this cartoon, Daffy] is really kind of almost like a sprite. He's just a little, almost elfin creature who's not really out to hurt anybody or has any ill will or malice toward anybody. He's just completely out of his mind."
- The Business Man later makes a cameo appearance in the bleachers in the 1996 movie Space Jam cheering for Michael Jordan after Michael wins. 
- It was only one of three non-Bugs Bunny cartoons from 1947 not to be reissued. The others were "Catch as Cats Can" and "Mexican Joyride".
- The cartoon was followed up in 1948 by "Daffy Duck Slept Here", wherein Daffy (this time as a fellow guest) again doesn't let a hotel patron sleep - in this case Porky Pig.
- Maltin, Leonard. Of Mice and Magic: A History of American Animated Cartoons, Revised, New York, NY: Plume, page 429. ISBN 0-452-25993-2.
- Paul Dini. A Pest in the House - DVD audio commentary - Looney Tunes Golden Collection: Volume 5.