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".