Opis: The film opens with a telephone operator connecting a call to the Hollywood Hotel. As the opening credits scroll across the screen "Hooray for Hollywood" is played by an unseen orchestra. The song continues as the action begins. We see several signs: "Clark Gable Beware!," then a trumpet player improvises; "Kay Francis Here He Comes!," then a saxophone player plays; "Leslie Howard Watch Your Step!," then a trombone player plays a lick; "Garbo I Tank You Like Him!," then a string bass player slaps his bass; "Olivia de Havilland Your Midsummer Nights Dream Is On His Way!," and then Benny Goodman (himself) improvises on his clarinet (all instrumentalists are members of Goodman's band). The camera reveals that each of these instrumentalists and many other members of the band are in a motorcade, with each person in a different car with a different sign plastered on the front of each car. They are parading, under police escort, to the St. Louis Airport. Once they arrive, they continue the song with Georgia (Johnnie Scat Davis) and Alice (Frances Langford) singing the lyrics; then, the band members also sing. The band is seeing one of its saxophone players, Ronnie Bowers (Dick Powell), off to Hollywood; he has signed a ten-week movie contract with Miracle Pictures; the studio's motto is: "Miracle Pictures Studio, If Its a Good Picture, Its a Miracle." As his plane taxies away from the loading area, the band launches into "California, Here I Come."
The next sequence is a montage of various Hollywood sights as "Hooray for Hollywood" plays in the background. Ronnie is met at the airport by Bernie Walton (Allyn Joslyn) from the Miracle Pictures publicity department. The studio photographer takes a couple of shots of his arrival, after which he is escorted to the Hollywood Hotel, where he'll be staying.
The scene switches to the hotel suite of film star Mona Marshall (Lola Lane) where the famous gossip columnist, Louella Parsons (herself), is interviewing Miss Marshall while she is being fitted with a gown to wear to the premier of her newest film. Mona is ranting and raving and thoroughly overacting about everything. She is the prototypical spoiled, self-absorbed female movie star. When she learns that someone else has been cast in the lead role of a film she had coveted, she refuses to appear at the premier of her film that evening. Instead, she and her assistant leave town.
The studio head is in a panic when he learns the star of his film will not appear at the premier. The studio publicity man, Bernie, comes up with a solution. Hell find a double to stand-in for Mona. After Bernie auditions several women, he chooses Virginia Stanton (Rosemary Lane) as Monas substitute (Rosemary and Lola Lane are sisters, so there is a definite resemblance). To escort her to the premier, he selects Ronnie Bowers, the new guy the studio has signed to a short term contract.
Bernie and the studios make-up crew take Virginia to Monas Hollywood Hotel penthouse suite and transform her into a Mona look-a-like. Ronnie is thrilled that his first night in Hollywood he will be escorting the famous Mona Marshall to her film premier. When he gets to the penthouse, a call comes from the front desk that Alexander DuPrey (Alan Mowbray), Mona's co-star in "Glamour Girl," is coming up to escort her to the premier. Bernie has told the maid not allow anyone except Ronnie into Monas suite. When she hears that DuPrey is coming up, she panics. Ronnie, however, rescues the situation by socking DuPrey to keep him out of Monas suite.
At the premier at Cathay Circle, the announcer interviewing the stars as they arrive is future President of the United States, a very young Ronald Reagan.
After the premier, Ronnie and Mona/Virginia return to the Hollywood Hotel's Orchid Room for a party. As they dance together, she tells him shes tired of all the photographs and autograph seekers, so they walk out into a garden area where they sit by a fountain pool. As she dunks her toes into the cool water, he sings "I'm Like a Fish Out of Water." After he sings a chorus, she sings as they dance together in the fountain. During this number, Monas sister, Dot (Mabel Todd), chases Fuzzy (Ted Healy), who is trying to avoid her, into the garden where they sing a chorus of the song. Ronnie and Mona/Virginia hide when they see Dot and Fuzzy coming (Virginia is certain Dot will realize that she isnt Mona) and turn on the fountain which soaks both of them. As the song concludes, Ronnie and Mona/Virginia kiss.
When Mona reads the morning paper and sees a photo of Virginia posing as her at the premier, she explodes. She rushes to the studio and demands they fire both Virginia and Ronnie. When Ronnie arrives for his appointment with the head of the studio, Mona storms out of the office and slaps him when he calls her darling. Bernie informs Ronnie that the studio head has fired him. Completely confused, Ronnie goes with Bernie to a coffee shop where Virginia is the waitress, which confuses Ronnie even more. Before anyone can explain, he stalks out of the coffee shop. When he encounters Mona as she is leaving the hotel, she slaps him again. Finally, Bernie explains to Ronnie that it was Virginia he escorted to the premier. Ronnie and Virginia are out on a sightseeing date when they climb over a hill to the Hollywood Bowl. To illustrate the Bowl's exceptional acoustics, Virginia sings "Silhouetted in the Moonlight" from the stage while Ronnie remains on the hill.
After being summarily fired, Ronnie acquires Fuzzy as his manager. Ronnie and Fuzzy see Benny Goodman, Alice and Georgia on a Hollywood street corner and learn that the band has been booked at the Hollywood Hotel.
Ronnie and Fuzzy find work as waiters at Callaghan's, a drive-in restaurant. Virginia comes by the drive-in and agrees to wait for Ronnie until he gets off.
The scene switches to the Orchid Room where Benny Goodman introduces the song, "Let That Be a Lesson to You." Georgia sings the lyrics, but suddenly the scene switches back to the drive-in where Ronnie sings a lyric about himself as he serves Virginia a milk shake. Later, Virginia and most of the drive-ins customers also join in the song. Dot, who also shows up at the drive-in, sings a chorus to Fuzzy.
A director from Miracle Studio happens to be a customer at Callaghan's and hears the performance. He tells Ronnie he wants to hire him. Virginia tries to talk Ronnie and Fuzzy out of quitting their waiting jobs, but they wont listen.
When Ronnie and Fuzzy arrive at the film location the next day, they discover that the director wants Ronnie to dub the singing voice of Alexander DuPrey.
In a rehearsal sequence, Benny Goodman and His Orchestra play "Sing, Sing, Sing," which features Gene Krupa's marvelous extended drum solo and solos by Harry James on trumpet and Benny Goodman on clarinet. Then, Goodman's quartet (Lionel Hampton on vibes, Teddy Wilson on piano, Gene Krupa on drums and Goodman on clarinet) plays "I've Got a Heartful of Music." At the preview screening of Mona Marshall and Alexander DuPrey's film "Love & Glory," Ronnie sings "I've Hitched My Wagon to a Star" as DuPrey mouths the lyrics on screen. Even though Ronnie's voice doesn't fit DuPrey, everyone is impressed with DuPrey's vocal abilities. Louella Parsons asks him to sing on her radio show. He accepts, but later panics when Mona asks whose voice he will use. Ronnie has disappeared and the studio cant locate him. They call Virginia for help and she finds him working as a waiter at Callaghan's drive-in again. Ronnie, however, doesn't want to dub for DuPrey any more. If he sings, he says, he wants it to be his face on the screen.
Virginia cooks up an idea. Again posing as Mona, Virginia picks up DuPrey to accompany him to Louella's radio program. Fuzzy is the chauffeur and Mona's father, Chester (Hugh Herbert), is also along to help. They drive until DuPrey demands he be let out of the car. They gladly let him out, but by then, it is too late for him to make the radio show.
The CBS broadcast begins with Raymond Paige and His Orchestra (themselves) performing a reprise of "Silhouetted in the Moonlight." Jerry Cooper, Paige's male vocalist, and Alice are the vocal soloists. Next, Paige, his instrumentalists and a chorus perform "Dark Eyes" in their jazz symphonique style. Then, Louella Parsons introduces Ronnie and Mona to perform a scene from "Love & Glory." During this sequence, Ronnie reprises "I've Hitched My Wagon to a Star."
Everybody (Ronnie, Virginia, Georgia, Alice, Mona, Jerry, Dot, Fuzzy, and the chorus) gets involved in the finale, "Sing, You Son of a Gun," which evolves into a final reprise of "Hooray for Hollywood."