Credit: Gene Page/AMC Photo: Sasha Peers Outside in The Walking Dead Season 4, Episode 2: “Isolation”

The Walking Dead Season 4 should air with a pop-up feature reminding us who the heck some of these people are.

A bunch of former Woodbury residents joined the prison at the end of Season 3, but Daryl Dixon (Norman Reedus) and Rick Grimes (Andrew Lincoln) have also been bringing home strays, like Bob Stookey (Larry Gilliard Jr.) and apparently the now-dead David from "the Decatur group."

Plus we have Dr. S. — who said hi to Daryl during mealtime in the Season 4 premiere and became the center of the medical action in Episode 2, "Infected." A sneak peek for Episode 3 shows sick Sasha saying she needs to find Dr. S.

So Dr. S is now a biggish part of the story. Who is the guy? His full name is apparently Dr. Caleb Subramanian and he's played by actor Sunkrish Bala.

What else do we know? Not much. But we do know he's not even the first Dr. S. Remember the female Dr. Stevens featured in Woodbury in Season 3? Maybe we just always need a Dr. S., and now that she's ... somewhere, maybe dead ... he's here.

The new Dr. S. may be a fresh take on the male comic book character named Dr. Stevens, who was also from Woodbury and got to know The Governor and Bob Stookey.

We've been so caught up in wondering if Bob is a spy for The Governor, but we have to stay open to the possibility that The Powers That Be are using Bob as a red herring. Maybe Bob is harmless and Dr. S is trouble? Maybe they're both in cahoots with The Governor, using different tactics to help him from the inside? Or maybe they're both decent guys and not connected to the burned people of Episode 2 or the rats at the fence or anything else.

What do you think of Dr. S? Can we trust him? Do you not care, since all these newbies seem to be dying off anyway?

The Walking Dead Season 4 airs on Sundays at 9 p.m. ET on AMC.


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