By the third film in the Blondie Series, the producers must have realized they were in a peculiar situation. In order to milk the popularity of the series for all it was worth, they had to deliver a recognizable product, and so in each installment there are a number of common plot points. Dagwood makes towering sandwich, runs out the front door and knocks over the mailman, and losses his job, meanwhile Blondie suspects that Dagwood has fallen in with another woman, sees red, forgives him, and plot to get his job back, and, of course, everything turns out alright in the end. But they producers must have also realized that the public would not go on paying to see the same film over and over again, so in the third installment, they began exploring different genres while keeping the same basic story arch. Blondie Takes a Vacation plays like a weak whodunit, with the crime only coming in the final stages of the plot.
The Bumsteads are finally allowed to go on their long-awaited vacation by Dagwood’s boss Mr. Dithers. Typically, nothing goes as expected, and rather than getting to rest and relax, the whole family finds themselves scrambling to help an older couple save their failing hotel. Aboard the train on the way to the resort, the Bumsteads raise the ire of a man (character actor Donald MacBride, who specialized in play just such brash characters), who later turns out to be the manager of the Lake Hotel where they have reservations, and he refuses them a room. The family seeks refuge in a run-down inn, which the Lake Hotel manager is ruthlessly trying to take over. A subplot involves a kind gentleman who happens to be a serial arsonist, upon whom suspicion falls when the Lake Hotel burns to the ground. Dagwood and Baby Dumpling join forces to prove to the police who really lit the match.