The Flash | The Flash Official Season 4 Extended Trailer

The team is clearly still trying to deal with the loss of Barry, particularly Iris, and trying to decide if they should still have faith that he will or can come back.
Cisco and Wally have taken it up upon themselves to protect the city and are not doing a spectacular job as Cisco points out and Cisco wants to try to bring Barry back.
Iris is focused on moving forward and is apprehensive to trying to get Barry back. We see Cisco with a device to try to get Barry back and Iris looking at a Speedforce storm.
We then see the scene of Barry's feet in the middle of nowhere with Speedforce running through his body and the scene of the team meeting Barry in the police Department.
I think this Samuroid battle might be a flashback to months before Barry returns as I think Barry's old suit will be destroyed by the Samuroid and give time for Cisco to make a new one.
If it is not a flashback then Cisco, as a way to cope and to have hope that Barry will be back, started making the new suit shortly after Barry entered the Speedforce
The Speedforce writing that Barry is doing is interesting and I hope it leads to something during the course of the season.
Also here's hoping Barry learned some new tricks while in the speedforce or the speedforce writing is a way to unlock some new abilities once they decode it.

UPDATE: I made a YouTube video about this trailer and breaking down the description for Episode 1 check it out here:

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