During Discovery's first season, I had a theory that the Romulans were behind everything (T'Kuvma's mission, pushing the Klingons against the Federation by providing cloaking technology), which I still believe but is less and less likely to ever be shown to us, especially now that the Romulans (seem to be)/are the Big Bad of Picard.
But after watching the two episodes of Picard, I decided to reverse this theory and wonder: What if the Klingons are the bad guys of Picard? And in doing so, I stumbled upon a dark, horrible theory that I will get to in a little bit.
So, first: how and why would the Klingons be the bad guys in Picard? We see that the Romulans, specifically the Zhat Vash, are doing nefarious things. But it's all been shown to us and tied up in a neat bow. Something more must be revealed, beyond Maddox, the Synths, the Romulans, and their connection with the Borg Cube.
In All Good Things, which Picard is heavily based on (combadges, Picard's illness and retirement), the fate of the Romulan people is to be conquered by the Klingons. In the current continuity, the Romulan star blew up, and they apparently survived the conquest somehow. Could the Klingons be attempting to conquer the Romulans? Could they be behind the supernova?
No. There's no evidence of that. They did lose their moon to mining, but it's unlikely the Klingons could do an unprovoked attack on the Romulan star, and the Romulans apparently had two years to flee after the star begin acting wonky.
And there's been no mention or reference to the Klingons except for one: Worf. Worf was referenced in the second episode as a comrade of Picard's who would jump at the chance to help him (I dispute this, but Picard doesn't). In the first episode, we actually see an image of Worf (a still from Sins of the Father, I believe) alongside Picard on the news. So they're subtly reminding us of Worf's existence more than any other TNG character (except Riker).
In All Good Things, Worf was a Klingon Governor. He had a similar posting in Star Trek Online. This conflates with DS9's conceit that he left Starfleet (or at least, active service) following the Dominion War, and would be at the service of the Empire. As a respected member of the Chancellor's House, this is likely.
So, when Worf inevitably appears (note:
CBS has been surprisingly emphatic that Dorn is not in Picard, despite him accidentally signing an autograph for the cinematographer alongside all of the Picard cast...), his role will likely be in connection to the Klingon Empire and the Klingon conspiracy.
Worf hates Romulans. They murdered his family and attacked his colony when he was a young boy. But he's a moral man, you say? Well, every other episode, he had to be pushed into doing the ethical thing (note: not Klingon honor) when it came to donating blood to a Romulan or not murdering that kid. But he still killed Duras. He will set aside his Starfleet values for the values of his House, his people.
Twenty years surrounded by Klingons may have warped Worf's mind. Starfleet values may hold little to him, in regards to the Empire. He respects Picard, as his superior for so many years, but if Picard were to ask him to work with the Romulans, he will say no.
Worf is a security expert. He's also a strategist. He knows the costs of war, and how to wage one. The Romulans are in disarray, some clinging to Borg cubes, some hiding in plain sight within Starfleet. Now is the time to strike. Worf, and his allies in the Klingon Empire, are planning to conquer what parts of the Romulan Star Empire they don't already control.
But that leads to an insidious thought. What if Worf is behind the synth attack, in order to stop Starfleet from helping the Romulan people? What if he kidnapped Maddox (who he knew from the TNG episode) and used him to reprogram the synths? What if Worf actually used a tricobalt Dominion weapon to destroy the Romulan sun (which he nearly witnessed in DS9)?
Worf is the most prolific Star Trek character. He has seen everything that went on in TNG and the back half (good half) of DS9. He knows the Borg, he knows the Dominion. He has defeated both. He is the franchise's biggest proponent of overwhelming force, kept in check for a time by Picard and a little by Sisko. But no longer. With the Chancellor's approval, Worf has free reign to do as he pleases for the good of the Empire. For his own twisted good of Starfleet. And against the Romulans he despises with all his soul.
La Forge is alive, despite evidence in the comics to the contrary. I think somebody called and gave him a heads up.