As the episode progresses, the story spirals out of control:
Marshall tells the guys he was held up at gunpoint by a man. [S5E19] Zoo or False
After the mugging, Marshall is embarrassed to tell Lily he was robbed by a person, fearing she’ll think he’s "weak" and insist they buy a gun for protection. To avoid this, he claims he was actually at the zoo. The Escalating Lies As the episode progresses, the story spirals out
The "Zoo or False" theme highlights Marshall’s desire to protect Lily’s sense of safety while balancing his own pride. As the episode progresses
To stop Lily from buying a gun, he claims a monkey cornered him and stole his wallet.
Barney, sensing a great story, tries to get Marshall on a local news segment.