“You sent my brother Nicky to the big house.” 

Radar delivers the mail, including a package from Frederick's of Hollywood, to Hot Lips.

Radar: You know, I went through Hollywood on the way here. I think I saw James Cagney. [Imitation] Mmm, you sent my brother Nicky to the big house. Mmm. Cagney.

Hot Lips holds up lingerie, Radar whistles, she hides it.

Hot Lips (impatient): Is there anything else?

Radar: Uh, we're having a pool on the birth of a baby. Date, weight and sex, one dollar.

Hot Lips: I don't approve of gambling.

Radar: It's Col. Potter's grandchild.

Hot Lips: Six and a half pounds, the 25th, boy. Now scram!

Radar: Right. [By the door, he goes back to the Cagney impression] Mmmm. [She gives him a look, because he seems to be commenting on the lingerie, so he explains] Cagney. [Then he flees]

-- from “M*A*S*H,” S4, Ep14, “Mail Call, Again,” original air date Dec. 9, 1975, writers James Fritzell, Everett Greenbaum. I'm curious where the line comes from. It's not a Cagney line. He didn't have many brothers in the movies, and if he did they were usually straight-arrow ding-dings like Mike in “The Public Enemy.”