"Come good people, save our steeple," says the sign onstage as the audience files in for An Evening with Bertram Wooster, a banjo concert to benefit the Little Wittam church. Unfortunately, as the show is about to get underway, it is discovered that a frying pan has been substituted for Bertie's banjo (A False Start). Once he regains his composure, Bertie sets out, with the aid of the ever-present Jeeves, to salvage the remainder of the evening with an anecdote, at least until the arrival of a new banjo (Never Fear).

The story begins the day after Bertie has been arrested for abducting a police constable's helmet. The presiding judge, Sir Watkyn Bassett, vowed to remember his name, so Bertie gave him an assumed one - Augustus Fink-Nottle, one of his friends. Unfortunately, it turns out that Gussie has fallen in love with Bassett's daughter Madeline, and therefore can't have Bassett thinking he's a criminal when they are introduced. Therefore, he decides to taken on Bertie's name until the whole mess can be straightened out.

Another matter of concern, however, is an advertisement in the Times, announcing the engagement of Bertie to Stiffy Byng. This truly complicates matters, as Stiffy is Bassett's ward, and Gussie is posing as Bertie. If Bassett were to read this and believe that Bertie (Gussie) was engaged to Stiffy as well as courting Madeline, things could get ugly. So Bertie is forced to make the trip to the country to speak to Stiffy about the ad. (Travel Hopefully).

The trip does not go very smoothly. Along the way, Bertie runs down another friend of his, Bingo Little, who has been involved in a charity hike for hedgehogs to impress Ms. Honoria Glossop, Bertie's ex-fiancee. Bertie offers Bingo a ride, which he accepts, only to be thrown into a panic once they come upon Honoria along the road. Anxious not to be seen "cheating" on the walk, Bingo jumps in the trunk, and Honoria, who has twisted her ankle, takes a ride with Bertie. Along the way, old feelings begin to resurface...at least on her part. (That Was Nearly Us)

Having overheard the entire conversation, Bingo is furious with Bertie, who he claims was flirting with Honoria, and storms off. Bertie, meanwhile, heads to the Bassett estate to find Stiffy, where they have agreed to meet, in the maze. She tells him the reason for attracting his attention with the Times ad - she wants him help in a scheme to bring her and her love Harold together (Love's Maze). Bertie refuses, and Stiffy leaves him in the maze, which he is only able to escape with the help of Bassett, who recognizes him as "Gussie", the assumed name he had used in court.

Unfortunately, Bertie had inadvertently let slip to another visitor at the Bassett home that his name was in fact Bertie. When Gussie also enters the scene, the third party, Cyrus Budge, becomes very confused. Bertie attempts to throw him off the track (The Hallo Song), but eventually it becomes clear that something is not right. To save the situation, Bertie is forced to allow Gussie to keep his name, which he takes on the name of Bingo. Until, of course, the arrival of Bingo.

The hopefully confused identity-swapping trio call in the help of the only person they know who's smart enough to unravel this mess (By Jeeves). Jeeves instructs that the first order of business is to solidify the relationship between Gussie and Madeline, which is being threatened by the advances of Budge. Bertie takes on the role of messenger to convince Madeline that Gussie does love her, though he may not be able to show it (When Love Arrives). However, Madeline misinterprets his words, and believes that Bertie is the one in love with her, which infuriates Gussie.

Not very impressed with the outcome of that plan, Bertie takes out his frustration on Jeeves (What Have you Got to Say, Jeeves?). But things must get more tangled still before they improve - Stiffy and Harold convince Bertie to help them convince Bassett that Harold is a suitable match for Stiffy (Half a Moment). All it involves is a little burglary...

As Bertie enters the house for the faux theft, wearing a pig mask for disguise, he accidently happens upon Honoria, who tries to stop him. Soon the whole house is waked and is hunting the "housebreaker pig" (It's a Pig!). Just when it seems that all is lost, Jeeves finds the perfect solution, and everything works out for everybody...well, almost everybody.

Finally, the new banjo arrives, and Bertie is able to perform his opening number, Banjo Boy, with full supporting chorus.