As the Zephyr slides inexorably towards the centre of a time storm and certain destruction, only two of the Agents of SHIELD can save the day, as they find themselves caught in a time loop of which only they are aware.

“Groundhog Day but in space” is a hell of a concept for an hour long episode to try to pull off, but around that simple central premise this instalment of SHIELD manages to ang so much character development and so many ideas that the central premise by the end almost feels incidental.

Caught in the loop are Daisy and Coulson – everyone else unaware that they are living and re-living the same short period of time as the Zephyr is dragged towards a hole in time and space that will destroy it and all on board utterly, wiping them from having ever existed in the first place. If you’ve seen Edge of Tomorrow – which might be a better reference point here – then you’ve got the basic idea. Insurmountable problem, repeated resets, and the frustration of getting up to speed each time.

However, the episode also plays around with the idea – it’s not the strictly linear progression of the Cruise blockbuster – there are setbacks, deviations and alternate trails of thought that mean it never risks getting boring. And then halfway through proceedings, the writers throw in another curveball, adding a layer of mystery to the immediate problem and letting the whole gang have a bit of fun.

Clark Gregg is absolutely on form here having the time of his life as the frustrated mentor having to go through loop after loop and explain things over and over, using every ounce of his signature Coulson wit – that dry, snarky lightness that papers over a depth of feeling and pain which radiates from him. Chloe Bennet, for her part, gets to let her hair down from the generally serious tone that’s been forced on her character in recent seasons, even as she is the only one able to save her and her crew from total destruction. There’s even a hint towards a romance that’s been gently brewing for a while now, not that she really has the time, so to speak.

For an episode that’s dealing with another ticking clock towards annihilation, it’s mostly quite fun and pacey, but then it really steps down a few gears with an ending that reverts to some serious emotional insight and a genuinely moving turn of events. It might be cliché, but this really is an episode that brings pretty much everything to the table.

Verdict: A hackneyed idea given new life simply by way of how it’s executed and who is doing it. Brilliant stuff. 9/10

Greg D. Smith