The Assassini
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A Catholic reporter is murdered after being on the track of a story involving the church and World War 2. Her brother and her best friend come together as they try to pick up her clues and see what she was killed for.
Bit of a slow burner, the last third is when it starts to pick up as more is revealed and it heads toward the final reveal. (Which you'd probably guess by half way through).
Good characters, you're kept guessing about whose side they are on and what their motives are.