I Want An Answer

Brendan knew there was something going on that wasn’t quite right. The years he’d spent on the show had given him enough experience to know something was happening – and of course, he’d done the same thing quite a few times.

When something's not right, you want to know what it is.
Brendan knows what it is, and he knows it's true, but he has no solid evidence.

SCD.
(Heavily) implied Ian/Brian.