Just when we thought Marvel's 'Agents of S.H.I.E.L.D.' had made its most fan-pleasing cast in the form of nerd icon Patton Oswalt, the ABC 'Avengers'-adjacent series has tapped a Joss Whedon icon for its most on-point casting yet. 'Angel' and 'Dollhouse' alum Amy Acker will pick up horse-hair as Agent Coulson's infamous Portland cellist, but what brings the once-dead Agent back into her life?

Via TVGuide, Acker will first appear in the April 22 installment of Marvel's 'Agents of S.H.I.E.L.D.' as Audrey, whom fan-favorite Phil Coulson has been referencing as far back as 'The Avengers,' while Coulson's resurrection has often called into question the character throughout the first season as well. Described as "a talented musician turning heads in Portland," Audrey remains under the impression that Coulson died before the Battle of New York, and has no idea that Phil has returned to guard her from a distance when a super-powered threat from her past re-emerges.

As if that weren't exciting enough to 'Agents of S.H.I.E.L.D.' viewers and Whedon fans alike (Clark Gregg and Amy Acker also shared screen time as uncle and niece in 'Much Ado About Nothing'), subsequent weeks will see Victoria Hand (Saffron Burrows), Jasper Sitwell (Maximilliano Hernandez), Blake (Titus Welliver) and John Garrett (Bill Paxton) all returning to battle the menace of Deathlok, while ‘Heroes‘ star Adrian Pasdar will put in an appearance as ‘Hulkantagonist Glenn Talbot.

Marvel's 'Agents of S.H.I.E.L.D.' will return April 1 (not a joke!) with "End of the Beginning," but in the meantime, what say you? Is Amy Acker exactly the right fit for Coulson's oft-mentioned cellist? What other Whedon alum would you want to see join Marvel's 'Agents of S.H.I.E.L.D.'? Check out the latest preview below, and give us your thoughts in the comments!

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