S5 kind of blew me away. For these reasons.
I though the character dynamics, chemistry and delivery reached a whole new level in S5. I kept rewinding the paint can scene with River and Coe, as the way they delivered their reactions, cracked me up. So, just an added touch of humor throughout, as well.
The actors' demeanor and general appearance made them appear even more natural within their roles. It seemed like their skill level also went up a level. Didn’t think that was even possible.
I loved Coe’s progression, but oddly I couldn’t seem to take my eyes off of Saskia Reeves as Catherine Standish. I’ve seen her in other roles but, imo, she is just outstanding in this particular role.