Based on a short story by Jo Nesbø, “Killer Heat” is a neo-noir drama set in Crete. It's modestly entertaining, but it suffers from the same affliction as many movies in this genre; it's essentially an episode of Magnum PI or The Rockford Files expanded to two hours and set in an exotic location. There's the quirky protagonist/narrator who's hiding a secret of his own while investigating a murder whose "mystery" is telegraphed in the first 10 minutes.
Seriously, there is a reveal in the first act that anyone who has ever read or seen a noir mystery will immediately recognize, which predicts how the next 90 minutes are going to unfold. From that point on, it's pretty much just enjoying the beautiful Crete setting and ticking of the plot points as they emerge.
The primary actors, Joseph Gordon-Levitt and Shailene Woodley, give it their best try, but there's just not enough meat to the story to make anything interesting or memorable. The brown vintage Mercedes might be the most noteworthy thing in the production.
Serviceable entertainment. Basically, fast-food noir.