Barry Allen is preparing for the birth of his daughter with Iris West, and the team is enjoying a moment of calm. Barry is suddenly transported back in time to the year 2000, the day his mother, Nora Allen, was murdered by the Reverse-Flash. He tries to use the Speed Force to return to his own time but finds himself unable to open a time portal despite running at super speed.

Barry visits the Central City Police Department and meets younger versions of Joe West and David Singh, who do not recognize him. He speaks with Joe to get contact information for a local scientist who might help him. Barry realizes he has arrived on the exact day the Reverse-Flash kills his mother. When Barry tries to approach his parents on the street, he is incapacitated by Eobard Thawne, the Reverse-Flash, and taken to a hospital under the care of Henry Allen, his father.

At the hospital, Barry, under an alias, has lunch with his parents, cherishing the moment. He then abruptly leaves to confront Eobard Thawne, who taunts him but denies having brought Barry back in time. Barry deduces this is the original Reverse-Flash, who plans to kill young Barry before killing Nora. Barry is careful not to reveal how the night will unfold.

Meanwhile, Joe and David investigate the site where Barry was attacked. Joe finds a strange blue crystal that possesses him when he examines it. Joe becomes hostile and attacks Barry, claiming he is not the new Negative Speed Force avatar but still wants to reduce Barry's impact on the timeline. Barry manages to free Joe and returns him to his car, but the crystal disappears.

Barry then returns to his childhood home, where he sees Eobard Thawne standing outside. Thawne recounts his origin and how the Flash ruined his life. Barry apologizes for inadvertently hurting him and offers Thawne a chance to walk away and have a better life. Thawne appears to consider this but ultimately rejects the offer.

Thawne runs into the house and starts zooming around the living room, intending to kill young Barry, just as he did years ago. Barry enters and sees his younger self watching the scene unfold. Barry signals his younger self to stop and then zooms him out of the house, depositing him safely in the street.

With young Barry safe, Thawne turns his attention to Nora Allen and kills her. He then tries to run back to the future but finds he cannot because he has used up his speed or time-travel ability. Barry confronts Thawne and thanks him for giving him the opportunity to spend one last day with his parents.

Thawne realizes Nora's death is a fixed point in time and that he is now stuck in the past. He vows to destroy Barry and everyone he loves, declaring his life's work will be finding ways to kill the Flash. Barry tells Thawne that the night has tortured him for decades but that he has now found peace. Barry thanks Thawne and says he will always be grateful. A blue light flashes, and Barry disappears.

Elsewhere, a man resembling Eddie Thawne is struck by lightning at Mercury Labs. He finds a file about Eddie's death and wonders who he is, hinting at future developments.

At the end of The Flash Season 9, Episode 10, "A New World (1)," Barry confronts Eobard Thawne (the Matt Letscher version) at his childhood home. Barry saves his younger self from Thawne's attack, but Thawne kills Barry's mother, Nora Allen. Barry accepts Nora's death and thanks Thawne for allowing him one last day with his parents before Thawne loses his powers and Barry is transported away again. Meanwhile, a man resembling Eddie Thawne is struck by lightning, hinting at future developments.

The episode's ending unfolds in a detailed sequence:

Barry arrives at his childhood home in the year 2000, where he finds Eobard Thawne standing outside. Thawne recounts his origin story and how Barry's actions ruined his life. Barry apologizes for the unintended harm and offers Thawne a chance to walk away and have a better life. Thawne appears to consider this briefly but ultimately rejects the offer.

Thawne rushes into the house and begins running around the living room, intending to kill young Barry, just as he did in Season 1. Barry enters and sees his younger self watching the scene unfold. Barry signals his younger self to stop and quickly zooms him out of the house, placing him safely in the street.

With young Barry out of harm's way, Thawne turns his attention to Nora Allen and kills her. After this, Thawne attempts to run back to the future but finds he cannot because he has exhausted his speed. Barry confronts Thawne and thanks him for giving him the opportunity to spend one last day with his parents before Thawne loses his powers.

As Barry is pulled away from the timeline again, the episode closes with a mysterious man resembling Eddie Thawne being struck by lightning at Mercury Labs. This man finds a file about Eddie's death and wonders about his identity, setting up future storylines.

In terms of character fates at this episode's end:

• Barry Allen survives, having saved his younger self and come to terms with his mother's death.
• Eobard Thawne loses his powers and is trapped in the timeline, powerless.
• Nora Allen is killed by Thawne, reaffirming the fixed tragic event in Barry's past.
• Young Barry is saved and placed safely outside the house.
• The mysterious Eddie-like man's fate is left open, hinting at new developments.

This ending emphasizes the inevitability of certain events in Barry's timeline while showing Barry's growth in accepting loss and his ongoing conflict with Thawne. It also sets up new mysteries for the continuation of the story.

For The Flash TV show, Season 9, Episode 10 titled "A New World (1)" produced in 2023, there is no specific information in the search results about a post-credit scene for this episode. The available search results primarily discuss post-credit scenes related to The Flash movie (2023) and the Season 8 finale of the TV show, but none mention a post-credit scene for Season 9, Episode 10 of the TV series.

The Flash movie (2023) has a notable post-credit scene featuring Barry Allen and Jason Momoa's Aquaman at a bar, which is unrelated to the TV show episode in question. The Season 8 finale of The Flash TV show had a post-credit scene setting up Season 9, but details about post-credit scenes for Season 9 episodes, including episode 10, are not provided in the search results.

Therefore, based on the available information, The Flash Season 9, Episode 10 "A New World (1)" does not have a known post-credit scene or it has not been documented in the sources found.

Barry meets the original Reverse-Flash, Eobard Thawne, in the past near his childhood home. Thawne recounts his origin and his grudge against Barry. Barry offers Thawne a chance to walk away from his plan to kill young Barry, but Thawne refuses. Thawne then attempts to kill young Barry as he did originally, but Barry intervenes and saves his younger self. Thawne kills Nora Allen instead and loses his powers afterward.

Barry is transported back to the day his mother, Nora Allen, was killed. He visits his parents and has lunch with them under an alias but leaves abruptly due to anxiety. He also says goodbye to them before being transported away again. This journey gives Barry a sense of peace about his mother's death.

Joe West finds a mysterious blue crystal that possesses him, causing him to act under a dark influence. He is hospitalized but later freed by Barry. Joe also helps Barry by providing contact information for a local scientist and investigates the site where Barry was attacked.

Khione continues to discover and understand her powers. Chester Runk creates a new suit for Allegra Garcia, and Allegra receives her first suit. Cecile visits Joe at their new home, and Allegra and Chester explore their relationship further. Iris West receives a Pulitzer Prize nomination for her article.

A man resembling Eddie Thawne is introduced at Mercury Labs. He is struck by lightning, finds a file about Eddie's death, and wonders about his own identity. This suggests a resurrection or new incarnation of Eddie Thawne, setting up future plot developments.

The Flash Season 9, Episode 10 ("A New World, Part 1") is generally suitable for a family audience but may contain some scenes that could be upsetting or intense for young children or sensitive viewers.

Potentially objectionable or upsetting aspects include:

• Violence and Threats: There are scenes involving confrontations with villains, including threats of harm and some physical violence typical of superhero shows. For example, a character attempts to harm a young version of Barry, and there is a significant emotional moment involving the death of a character, which may be distressing.

• Emotional Intensity: The episode deals with themes of loss, tragedy, and emotional struggle, particularly related to Barry's past and family. These themes are handled with emotional weight and could be upsetting for sensitive viewers.

• Mild Language and Tension: While not explicitly detailed in the sources, the show's usual tone includes some tense dialogue and mild language consistent with a TV-14 rating, which is typical for The Flash series.

Overall, the episode maintains the superhero action and emotional drama expected from the series but does not include graphic content or strong adult themes that would make it inappropriate for older children or family viewing with parental guidance. Sensitive viewers or very young children might find some scenes emotionally intense or mildly frightening due to the villainous threats and character losses.