A "Blood Simple" question

Just caught the last half on TCM last night. One thing puzzled me: M. Emmet Walsh was reaching around to, and opening, the window in which his hand got stabbed. Why was he reaching around there? I’m sure the question makes no sense to anyone who hasn’t seen this movie.

oops

Should be pretty obvious unless you came into the film only moments before the event.

Anyway, here’s what you missed. Link

I said last half, but actually only the part after the guy gets sniped, and she breaks the light bulb. Ok, he reaches out his arm to the next window over. He manages to lift the other window and reach in. If he was going to reach further in than that, he’d have to have arms like an orangutan. Was he supposedly reaching for the door knob in a door between the two rooms?

I think the question is “why did he reach around the window instead of just walking out of the bathroom and searching for her?” I think the room next door that she had climbed into through the window was part of another apartment, so he was planning on climbing into it as well.