Episode 4 of Tales of the Jedi begins at the Jedi temple, as Count Dooku sneaks through to the archives suspiciously. He deletes everything to do with Planet Kamino, and shuffles away.
It would appear that Qui-Gon has encountered a Sith Lord off on Tatooine, which has become the talk of the town in the council. Word travels fast, and as Qui-Gon returns, Dooku questions what happened. Master Yaddle is there to oversee proceedings and listens as Qui-Gon sings the praises of Obi-Wan, whom is now by his side as an Apprentice.
Dooku bids his goodbyes to his former Apprentice, commenting how Qui-Gon has grown so fast and reminiscing on old times. The council are leaving for Naboo but Dooku refuses to leave with them. He’s decided to let Qui-Gon go as he’s become one with the force now.
Dooku confronts the Emperor in secret some time later, claiming that Darth Maul has gone too far in killing Qui-Gon. Yaddle overhears their meeting, where Dooku confirms his betrayal and destroying everything he’s built. Yaddle comes out of hiding and tries to talk Dooku around but it’s too late, he’s fallen to the Dark Side.
With the Emperor watching on, Dooku and Yaddle both fight it out with lightsabers, eventually leading to Yaddle’s demise.
Understanding the spark that led to Dooku’s demise is a nice way of contextualizing what happened and understanding that the bitter pain he suffered at the hands of Qui Gon’s death, ended up being the tipping point to work against the Jedi.
Still, his ties with the Emperor before that have been well orchestrated and this anthology series has actually done a pretty admirable job of showing all of that, with Qui-Gon as a young Apprentice and Dooku growing more bitter and angry as time has gone on.
Ultimately though, the episode ends really well and the storytelling here is great.