The story of "Birdcage on My Foot" is as culturally relevant to the early 1960s as they come. The episode centers around heroin addict Arnie, who Tod and Buz have committed to help through the early stages of kicking his habit. In particular, the comments made by a Boston police lieutenant are particularly telling about the culture. He remarks that drugs have been glorified as an inspiration to beatnik poets and aspiring musicians, but that drugs bring not rainbows, but truly harrowing, life altering effects. This officer reflects the thoughts of the dominant culture of the time and the cultural disconnect between the establishment and the counterculture.
Robert Duvall's gripping performance as Arnie, the heroin addict, gives a clear indication of why he became the critically acclaimed actor he grew to be. His portrayal seems very real, and he shows thorough attention to detail in the smallest aspects of his character. The interaction between he and George Maharis is particularly strong as Buz browbeats Arnie and then helps him through heroin withdrawal. It's nice to see Maharis's talents up against those of a star like Duvall.
Speaking of Buz, this episode reveals still more of the ever growing picture of his childhood. The viewer knows from the beginning that he's an orphan and that he grew up in the rough neighborhood of NYC known as Hell's Kitchen; this episode also reveals that Buz has seen the effects of drugs firsthand, though he did not use them himself.