The recap scene for this episode provides us with different music, perhaps to reflect the darker tone of the Future Trunks Saga/Black Saga. Picking up where we last left off, Future Trunks has come face-to-face with Black, who is revealed to be an Evil Goku (although he refers to Future Trunks as "Saiyan" quite a bit). Realizing that Black doesn't seem to be aware of the time machine, Future Trunks puts up a bit of a fight and then distracts Black with a Masenko (one of Gohan's attacks) and successfully uses the time machine. Black is notably surprised that he can no longer sense Future Trunks' energy signature.
We then cut to the Main Timeline, where a teacher is teaching Trunks and the Pilaf Trio at Capsule Corporation. When they take a lunch break, the time machine arrives and they get Bulma who recognizes Future Trunks and rushes off to let Vegeta know. Noticing the similarities between the two, Pilaf mistakes Future Trunks as Present Trunks' secret, older brother. Bulma finds the communicator Whis gave her to contact him so she can reach Vegeta and she's glad to see Goku is there too. Present Trunks raises his power level so Goku can lock on to it with Instant Transmission; Beerus & Whis decide to tag along with the Saiyan duo. Goku then uses Instant Transmission to reach Korin's Tower to get some Senzu Beans and the teacher decides to take a break after all the weirdness she's seen. In the Alternate Timeline, Black vows to hunt down Future Trunks no matter what it takes. In the Main Timeline, Goku returns to Capsule Corporation and Bulma gives Future Trunks a Senzu Bean. The episode ends with Future Trunks attacking Goku, thinking he is Black due to PTSD and the last time he saw this Goku was when Cell killed him.
Sean Schemmel had mentioned before that he always wanted to play Evil Goku and it looks like he gets his wish thanks to this saga. Although Black seems to be Goku in some capacity, it is strange that he calls Future Trunks "Saiyan" as if he weren't one too and he is wearing a single Potara Earring, which is usually associated with the Supreme Kais. The teacher's reaction to all the weird stuff going on was pretty funny. Seeing Future Trunks use the Masenko was rather heartwarming since it references how Future Gohan was his mentor. I continue to look forward to watching this saga.
Behind the scenes, the animation studio messed up on Bulma's hair color. Then when Future Trunks came, they kept his hair purple. So when Toriyama did redesigns for Super, he did Future Trunks with blue hair.
Yeah, it was a similar situation. I can't remember if he was consistent with hair color on the manga covers and what not but he didn't tell Toei until later on that all pure Saiyans had black hair but here and there they ignored that like in the Bardock special.