Key facts are so clear to Tom Mathias

(Trying to say this without ruining the story for anyone who's not seen it already.)

Season one, episode two, near the end, the perpetrator has been identified but has escaped, and the task now is to find him.

Mathias, knowing where the perp must be, gets up and off he goes to get him. DI Rhys objects. In the brief moment it takes him to exit the scene, Mathias tells Rhys how he knows where the perp is. Rhys hesitates and Mathias is gone, just that quick. Now Rhys knows, and we know too.

Turns out Mathias was right, of course. He's the Jason Bourne of crime solving.

Detail in Hinterland

"Salem," says DI Mared Rhys, "by Sidney Vosper. The Devil's face is said to be hidden in the folds of the Welsh lady's shawl."

Source: Salem (Vosper painting) at Wikipedia

In the picture above, the woman in the shawl, the "main figure", is Siân Owen. In the picture below, the woman in the blue coat is Detective Sergeant Siân Owens. That can't be an accident.

Source: BBC One - Hinterland

For the record, the actress who plays DS Siân Owens is Hannah Daniel. The IMBd page on Hannah Daniel lists several roles where the actress is known as "Hannah Daniels".