Rosa Parks

In 1943, Montgomery, Alabama in America a woman called Rosa Parks boards a bus on her way home from work. She pays the fee but the bus driver demands she go around and get on the bus by the rear side entrance, as ‘coloured’ people are forced to sit at the back while white people sit at the front. She refuses, leading the bus driver to force her from the bus, he then closes the doors and drives off without her.

Eight years later the TARDIS materialises in an alleyway in the city. The Doctor was attempting to return her three companions, Graham O'Brien, Ryan Sinclair and Yasmin Khan to present day Sheffield and so is disappointed that they have not arrived where she intended, again. Before attempting to leave The Doctor finds that there are traces of Artron Energy in the area from another time travelling device and so decides to investigate.

While exploring the city they become involved in an altercation in a park, caused when a woman drops her glove and Ryan, noticing this, picks it up and attempts to return it to her. The woman's husband, Mr Steele, strikes Ryan in the face, warning Ryan not to touch his wife again. The Doctor, Graham and Yasmin try to help Ryan but Mr Steele racially insults Ryan. This reminds them of the racial discrimination against coloured people that is present during this time in America. Before things escalate further out of control Rosa Parks, who happened to be passing by, interjects, calming Mr Steele by promising to have his new suit tailored for him soon. With that, Mr Steele departs with his wife. The group thank Rosa, who proceeds to chide them, telling them how coloured people like Ryan and herself are discriminated against.

The Bus Driver

As Rosa Parks leaves, The Doctor quickly uses her sonic screwdriver to scan Rosa, finding Artron Energy is flooding around her. Meanwhile, a person called Krasko finds the TARDIS. Unable to get in, he blasts it with an energy weapon only to find it further shielded. Disgruntled, he gives up and moves on.

The Doctor and her three companions convene at a diner. There, Ryan and Yasmin discuss learning about Rosa Parks at school, awed by the fact she refused to give up her seat on a bus in 1955, resulting in her arrest and the subsequent Montgomery Bus Boycott, an event that led to the end of racial segregation on public transport in America.

Arrival in Montgomery, Alabama

Reading a paper The Doctor discovers that Rosa Parks has yet to commit her act and that they have arrived the day before. Concerned, the group wonder what to do. Because Ryan and Yasmin are not white the group discover that they are not welcome in the diner and so are forced to leave the premises.

Tracing the Artron Energy, the group locate, in a warehouse, a suitcase of equipment from the future meaning another time traveller is present, but are unable to learn more when its owner, a rehabilitated murderer named Krasko, starts firing at them with his temporal weapon forcing them to flee. They take refuge at a motel for whites-only. There The Doctor theorises that Krasko is attempting to change history by ensuring that Rosa Parks never had to refuse her seat on the bus.

Leaving her friends to research everything behind the critical moment regarding Rosa Parks, The Doctor returns to examine the suitcase's contents, before using it to shield herself from Krasko who suddenly returns. The Doctor learns that Krasko seeks to change Rosa Parks' life, since his neural implants prevent him from killing any living being.

A Walk in the Park

Unable to convince Krasko to abandon his plan, despite destroying the vortex manipulator he used, The Doctor and her companions focus on thwarting his scheme by ensuring that Rosa Parks refuses her seat to Blake at the appointed time, under the exact same conditions of the incident. Although Krasko works to counter their efforts, the group stay one step ahead of him, making certain to keep history on track.

Ryan does his best to remove false notices at bus stops, put up by Krasko to put people off using the bus, when he encounters the criminal blocking the bus route with a car. Ryan learns that Krasko’s actions are motivated by his deeply racist views, and so Ryan uses the displacement device that Krasko dropped to send the criminal into the past to stop him completely. Removing the blockage, he and the others re-join The Doctor on the bus as passengers. As the moment arrives, The Doctor realises they have become integral to events, and is forced to keep them aboard the bus.

After witnessing Rosa Parks being arrested by the police for violating segregation laws, the group return to the TARDIS knowing that history has been kept intact. Back in the TARDIS, The Doctor reveals to her companions that they have ensured that Rosa Parks will go on to become a living icon for freedom.

The Doctor then takes her companions, in the TARDIS, to see an asteroid, informing them that it is named ‘Rosaparks’.