Nathan Fillion

Dear sirs:

Time to get serious. You’ve had a half dozen or so great in-joke winks to “Firefly” (including, most notably, the Halloween episode that had Nathan Fillion back in Mal’s outfit) but now it’s time to take it to the next level.

You need to start casting other actors from “Firefly” in “Castle.”

You need a new guy in charge of the squad room. Bring in Ron Glass. Hell, call him “Harris” so we can have a “Barney Miller” connection as well. Alan Tudyk as a college buddy suspected of killing a friend with a bow and arrow (since he’s voicing Green Arrow in “Young justice”). Adam Baldwin as a homeless guy wearing that funky knit cap while eating a Subway sandwich. Jewel Staite as a mechanic. Morena Baccarin as a former love interest from another country seeking a green card because she’s (wait for it) an illegal alien. Gina Torres as an army sergeant. Sean Maher as a Doctor. Summer Glau as an actress whose shows keep getting canceled. And Mark Sheppard (who was the recurring character “Badger”) because apparently a law was passed dictating that Mark Sheppard has to show up at some point in every damned TV show I watch regularly. “Doctor Who,” “Supernatural,” “Burn Notice,” “Warehouse 13,” “Leverage.” He’s all over the place.

Oh, and have Joss Whedon write and direct an episode. Because we need an episode with crackling, snappy and yet occasionally oddly phrased dialogue and at least one three minute walk-and-talk with no cutaways. Plus we’ll get a scene where Castle’s teenager daughter kicks ass with a balletic form of kung fu.

Please get right on this. Thank you.

Peter David