Dolores (Evan Rachel Wood) now appears to be a completely different person. Not a Westworld host, but a human.

We can explain some of that by the ending of season 3. Let's review everything that happened.

Aaron Paul plays Caleb Nichols, a war veteran haunted by the memory of losing his friend Francis.

Caleb designed Rico to gather other outliers like him, but Solomon offered Caleb and Francis money to kill each other.

Maeve The key to the Sublime is inside Dolores' head, according to Engerraund Serac, who created Rehoboam with his brother, Jean Mi.

The season 3 finale saw Rehoboam destroy Delores' memories to get the key to the Delos data, but it never materialized.

Charlotte, Musashi, Martin, and Lawrence became replicas of Dolores.

In the season 3 finale, Bernard used the Sublime key, which is owned by Bernard and occupied by hosts including Maeve's daughter.

We may see Jean Mi in season 4 since he was sitting in the pod we saw in the penultimate episode.