In The Only Light In The Darkness, we finally get to put a name and a face to Coulson's lady love, "the cellist", first mentioned way back in The Avengers (and alluded to most recently in The Magical Place) - Audrey Nathan, played by Whedonverse stalwart Amy Acker.
It turns out that Audrey is the object of obsession (his "only light in the darkness") for one Marcus Daniels (Patrick Brennan), aka the energy-absorbing supervillain Blackout, an escapee from The Fridge thanks to last week's raid by Ward, Garrett and their Hydra cronies.
Meanwhile at Nick Fury's super secret base and still dealing with the fallout from Captain America: The Winter Soldier and the rise of Hydra, agent Eric Koenig (Patton Oswalt) insists Coulson's team goes through a lie detector test before they do anything else - which sparks his suspicions about Ward.
The background checks by Koenig reveal a nice tie-in to the Howlin' Commandos in Agent Triplet's backstory. An instantly likeable character, I hope he's a keeper for the second season, especially now we have this historical nugget to draw upon for future storylines.
Coulson, still not trusting May, takes Triplett (B.J. Britt), Fitz and Simmons off to track down Daniels - and save Audrey, who believes Coulson to be dead (since he was impaled by Loki in The Avengers).
Two parallel plots unfold in The Only Light In The Darkness: Ward's scheming at the secret base and Coulson's team's efforts to combat Daniels, whose powers have been boosted by his stay in The Fridge (presumably thanks to the influence of Hydra agents).
While the Coulson team get to face down an actual supervillain, and we get to meet Coulson's lost love (although she remains ignorant of his resurrection throughout), it's actually the weaker of the twin plots as Daniels is a rather two-dimensional villain and Audrey is just another "damsel in distress".
It's the storyline with Ward, Skye, May and Koenig back at the base that is the truly gripping thread of the episode, especially when Skye finally realises Ward is an agent of Hydra... and she's alone in the base with him.
Except for its revelations about "the cellist" (how she and Coulson met etc), the episode's real strength lies with Ward's double-dealings. My respect for him now - as a villain - is increasing and, while I want him to ultimately get his comeuppance, I hope he sticks around at least to the end of the season to screw with the good guys some more.