“The Wolf Inside” is episode eleven of season one of Star Trek: Discovery.
Discovery is in the Mirror Universe and, in the previous episode, “Despite Yourself”, Burnham, Tilly and Lorca were pretending to be their respective captains. Only Lorca is an outlaw after attempting a coup. Burnham was going to take him in, with Tyler accompanying her, so that they could find out what happened to the Defiant, which arrived in the Mirror Universe from their universe in the future, in “The Tholian Web”. Before they left, Tyler, concerned about his visions, went to see Dr Culber. Culber came to the conclusion that Tyler wasn’t Tyler – in fact, it looks like he’s Voq – and told Tyler he couldn’t leave. So, Tyler snapped his neck. On Mirror Burnham’s command, the Shenzhou, Burnham took Mirror Burnham’s old captaincy back and Lorca was placed in an agoniser.
Discovery is in the debris field undergoing repairs when one of the engineers hears something. Stamets, talking about a forest and holding the dead body of Culber.
On the Shenzhou, Burnham is saying she can’t rest here, not really. Mirror Saru enters her quarters to bathe and change her, only he’s a slave and has no name. Burnham is concerned that burying her heart, hiding her decency, pretending to be one of them, is killing the person she really is. She watches Mirror Detmer execute, by beaming in to space, three people for malicious thoughts against the emperor. As Burnham studies their ways it becomes easier to pass as one of them, and she fears becoming one of them. She’s telling this to Tyler, who tells her it won’t happen.
Mirror Saru enters with food and Burnham tells Tyler to check on Lorca. Burnham accidentally calls Mirror Saru, Saru, and realises her mistake, claiming she has decided to name him that. Afterwards, she gets a transmission from the Discovery; Tilly, in Terran Empire uniform. When the line is confirmed as being secure, Saru comes on it.
Burnham has accessed the classified files they need, but can’t transmit them off the ship without detection. They need the data; it’s their last, best hope to escape. Saru tells Burnham that Stamets’ condition hasn’t improved. He also wants to know if Burnham has encountered any Kelpians, as they are rare back home. Burnham lies, evidently not wanting to tell Saru she met his Mirror twin slave.
Burnham wasn’t the only one lying; Saru didn’t tell her the full truth, or what they think is the truth, about Stamets. He tells Tilly that he didn’t want to distract Burnham. They think Stamets killed Culber, and Saru says that Stamets could be a danger to them all. Tilly doesn’t believe Stamets killed Culber, because that isn’t Stamets. He’s been changed by what happened. Tilly wants to help Stamets, as this isn’t a medical issue, it’s a spore issue and no-one knows more about spores than Tilly.
Captain Maddox of the imperial flagship contacts the Shenzhou. The emperor has a mission for Burnham; they have found the location of the Firewolf, the Klingon leader of the resistance. The emperor commands the Shenzhou head there and kills them all. However, Burnham wants to infiltrate the rebel base before destroying it, so that they can gey the intelligence they need.
Lorca, when Burnham sees him, says she needs to wipe them out. Sometimes the end justifies terrible means. Burnham thinks his suffering may have influenced his judgement. The rebellion against the Terrans is the closest thing to a Federation the Mirror Universe has – and it’s led by a Klingon. They may find the means to successfully negotiate with the Klingons. Lorca tells Burnham that she and Tyler must beam down alone.
On Discovery, Tilly is telling Saru about how Stamets called her captain, then they came to the Mirror Universe where she is captain. He may have been getting glimpses of the alternate. She plans to restore the function of Stamets’ brain, using the spores.
Burnham and Tyler beam down to the rebel base. Wearing the uniforms of the rebels’ hated enemy. Unsurprisingly, they are fired on, but Tilly surrenders. They are taken to the encampment, and get a couple of shocks. The Firewolf is Voq, and seeing Voq causes problems for Tyler.
Burnham wants something from Mirror Voq, but he wants to check her out. Using Sarek, who likely gets a bit of shock from the mind meld. Tyler’s increasingly erratic behaviour becomes a serious problem, and Burnham is worried about it. On the Discovery, Tilly is trying to fix Stamets. And finally, the identity of the faceless emperor is revealed. There was a strong chance it was going to be a familiar face – and it is.