What are the main differences between the film and the novel it is based on?
Quick Answer
No information on a novel source is provided, so differences between the film and a novel cannot be identified from the available evidence.
Explanation
The only verifiable source concerns the 2026 film Supergirl directed by Craig Gillespie. It specifies the plot focus on Kara Zor‑El traveling across the galaxy to confront an adversary who harmed her pet dog Krypto. No mention of a novel adaptation, source material, or specific narrative differences is present in the documented evidence. Consequently, a comparison between the film and a novel cannot be made based on the supplied data. Any claim about differences would be speculative and unsupported by the verified reference. If additional sources become available, those could provide insight into how the film diverges from its literary counterpart.