Finally, I've been so thirsty for a genuinely good thriller. It's very rare I don't guess the plot, but this was very well done, reminiscent of the Tinker tailor era. It's a testament of the standard of all involved, as I've not really been a fan of the main actors, yet I genuinely feared for her safety and both gave exquisite performances. We need more of this now. Bring back decent cinema.