A typical "Clyde".
Clyde-n. Rat Pack slang; used as a reference to someone who is "Dullsville" personified. A Clyde might reveal his essence by wearing the color brown (especially shoes) after twilight.
And he's Alan's (Frank Sinatra) brother, straight outta:
He's repressed by his domineering, Jewish mother, and his overbearing, Jewish father. So obviously, he turns to his irresponsible, playboy older brother. The character Buddy is played by a B-actor named Tony Bill. He had small parts in a couple of other Sinatra movies. Here is Tony Bill's nndb page. My theory is he was cast because of his slight resemblance to Frank Sinatra, Jr.
At this point in the film, Frank brings out his secret acting weapon: the finger point.
Note the pinky ring. This is likely to be the one given to him by this man:
Giancana was a famous and powerful mafioso and boss of the Chicago Outfit from 1957-66.
He could wiggle that finger and point with flourish. You can tell baby brother is in awe.
Of course, Alan's bathroom is right out of the pages of early 60s era Esquire or Playboy.
Frank is no doubt using the very latest, state-of-the-art portable, electric shaver.
Just a glimpse of Sinatra's tan. He, like actor Yul Brynner, suntanned as much as possible. They had to wear less makeup on camera as a result.
As far as little brother, Buddy, is concerned, Alan's (Sinatra) "How to be a swinger" class is in full session. First order of business is to get him into some sharp, casual duds. And what did any self-respecting playboy in the early '60s wear while he was loungin'? Why, a sweater, of course.
Note the color.
Frank settles for a lighter shade of orange.
Now Alan performs a subtle, mini-lesson for Buddy, if he's paying attention. Back when men still carried handkerchiefs:
But that one would have been for personal use. What about one for the ladies?
Got it covered.
Alan implores Buddy to pull his finger. He might just be pointin', though. You know Frank.
The face-grabbing thing he does is getting a little bit odd.
At this point, the "How to swing" class moves over to the bar. Alan prefers getting his little brother sloshed than listening to his whining about life back home in Yonkers, with mom and dad.
C'mon, cheer up kid...booze!
Just focus on the booze.
In this shot, you can see detail of the forcep scarring Sinatra received moments after his birth. The forceps ripped off most of his left ear lobe, as well.
The doorbell rings. It must be a broad! No, its:
...pop, played by Lee J. Cobb, and he's pissed off with Alan, and looking for Buddy.