Betty had sent Hansen, dressed manifestly for the festival, to gloat over Vic in Lorrimer's place.

He was at it already.
"All turned out for the dance, Blondy, eh?
Takin' a girl ?" "Betty Neal," answered Blondy.
"The hell you are!" inquired Lorrimer, mildly astonished.

"I thought--why, Vic's back in town, don't you know that ?" "He ain't got a mortgage on what she does." Then, guided by the side-glance of Lorrimer, Hansen saw Gregg, and he stiffened.

As for Vic, he perceived the last link in his chain of evidence.

Hansen was going to a dance, and yet he wore a gun, and there could be only one meaning in that: Betty had sent him down there to wind up the affair.
"Didn't see you, Vic," Blondy was saying, his flushed face seeming doubly red against the paleness of his hair.