Let’s look at the first sentence.
I tucked my hands under my cheek, tried to picture the constable knocking on the door to Toby’s smokehouse, imagined the look on Toby’s face when he opened the door and found trouble on the other side.
We get a physical action which puts Annabelle in a thinking pose.
Then we see inside her thoughts, picturing a troubling event and then imagining Toby’s reaction.
Let’s look at a couple of examples using the same pattern.
I sat back under the eaves, wondered what would happen when Zhang brought out his prize cake for the mayor to try, imagined the noise he would make when he lifted the lid and saw that Luo had already eaten it the night before.
I tightened my grip on the shovel, pictured Queenie’s reaction when she found Kezia stacking rocks by the water’s edge, imagined how she might grab Kezia’s arm and pull her away to join the other girls in the weaving hut.