Actor Patton Oswalt has been cast in the role of Agent Eric Koenig on an upcoming episode of Agents of S.H.I.E.L.D.

Just when you start to think that Agents of S.H.I.E.L.D. has come to the end of their list of exciting guest stars, a new casting is announced that assures even more awesomeness to come.

This time, the casting in question is geek celebrity Patton Oswalt of King of Queens. Marvel.com has announced that Oswalt will play S.H.I.E.L.D. agent Eric Koenig, a character from the Marvel comics universe who came to prominence during the fictional 1940s. The character’s story line may be adjusted for Agents of S.H.I.E.L.D., however, as in the first image of Oswalt as Koenig, the agent appears to exist in the modern world.

As an established comic book enthusiast and fan of Agents of S.H.I.E.L.D., Oswalt was thrilled to be called in for the role of Agent Koenig. “I got a call from my agent saying they want you on Marvel’s Agents of S.H.I.E.L.D., and I said ‘hell, yes,’” the actor told Marvel.com.

Having previously worked with executive producer Joss Whedon on Dollhouse, Oswalt was excited to be on tap for another of the geek legend’s projects. “I’m lucky that I’m visible enough that they wanted to bring me in to play this character,” he said. “I guess I wasn’t too annoying [on Dollhouse] and they decided to put me on another one of his shows.”

As mentioned above, Oswalt is only one of several exciting guest stars to join Agents of S.H.I.E.L.D. Bill Paxton made his debut as Agent John Garrett (“One of my favorite Marvel characters,” Oswalt says) in the episode “T.A.H.I.T.I.” and Jaimie Alexander reprised her role as Lady Sif in the show’s most recent episode. Heroes‘ Adrian Pasdar will also be appearing in an upcoming episode as Colonel Glenn Talbot, a presumed foe to Coulson’s plucky team of agents.

Paxton will return as John Garrett in Agents of S.H.I.E.L.D., season 1, episode 16, “Beginning of the End.”

Agents Garrett and Triplett are back to help Coulson’s team track down S.H.I.E.L.D.’S nefarious enemy – the Clairvoyant. But will Deathlok destroy them all to protect his master’s identity?

In addition to Garret, J. August Richards will appear again as Deathlok. On the other side of the coin, Saffron Burrows will return as Agent Cynthia Hand, Maximilliano Hernandez will appear as Agent Jasper Sitwell, and Titus Welliver will reprise the role of Agent Felix Blake.

Agents of S.H.I.E.L.D. season 1, episode 16, “Beginning of the End,” will air on April 1 at 8:00 p.m. on ABC.