The writer behind "Route 66" -Stirling Silliphant, loved strange titles and more importantly was immensely creative in framing his stories in unusual ways. "The Man on the Monkey Board" refers explicitly to a sort of "Crow's Nest" job on an offshore oil rig, standing 125 feet above the rig's deck to do a dangerous job.
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He's dealing with a very serious subject, the job of Nazi hunters -topical at the time (Eichmann was arrested in Argentina in May 1960, 5 months before this episode was broadcast). Yet he rather cleverly sets the story and next destination of our wandering pair Milner & Maharis at an oil rig off the shore of Venice, Louisiana (majestically filmed on locations courtesy of Shell Oil),
That's where Lew Ayres, famous historically for his Pacifist beliefs in real life, plays the reluctant but dedicated agent searching for a Nazi who can be identified by his handwriting, after a letter turns up, now in Lew's possession. By happenstance M&M are assigned as roustabouts on the rig arriving in the same crew as Ayres and befriend him, though Milner is immediately suspicious of the older fellow.
The vast scale of the rig plus its title hint at the highly dramatic climax of the piece. Like Hitchcock or more generally the Bond films, having a magnificent, stiking setting goes a long way toward maximizing suspense and thrills in storytelling (see: Mount Rushmore for Hitch's "North by Northwest"). The oil rig is clearly arbitrary here, but Silliphant loves to utilize strange and often cryptic elements in his work.
Many things are atypical here, first the all-male cast, not strange but often tied to genres like a submarine movie; the really grimy, unappealing nature of the labor, paying only $1.70 an hour, at odds with the freedom the boys are always seeking, as they are literally trapped on the rig, accessible only by a helicopter shuttle (wouldn't Liev Schrieber be perfect casting for a remake in the Ayres role, as an Israeli agent fresh from his Blade helicopter commercials?). Also, the usual cultural clash is largely absent, as the boys are not exposed to an insular local or ethnic community, but instead the closed-off specialized profession of the roustabouts slaving on the rig.
A brilliant touch during the mystery/suspense portion of the show in which we wonder what Ayres is up to, has the classic German song of the Nazi era "Lili Marleen" quietly but insidiously introduced on the soundtrack as a hint of the revelation of Ayres will make.
Ayres, fully capable of reciting Silliphant's required soliloquies on the human condition, does a very fine job, and M & M are solid in a show in which they are more the bystanders who become involved in a larger story (Hitchcock-style) rather than the central players of Ayres versus the Nazi.