Ep 5. The Poison Sky

The fourth season of Doctor Who (2005) continues with the sixth episode titled "The Poison Sky." In this episode, the Doctor and his companion Donna find themselves on Earth, in the midst of chaos as the world prepares for war against an alien race known as the Sontarans.

The Sontarans have taken control of the world's military forces and are using them to launch a full-scale attack on Earth. The Doctor and Donna must work together with a group of soldiers to try and stop the Sontarans before it's too late.

As the episode progresses, the Doctor and Donna discover that the Sontarans are not the only threat they face. They must also deal with a group of humans who have formed an alliance with the aliens in order to further their own interests.

The tension and stakes continue to rise as the Doctor and Donna race against time to stop the Sontarans and their human allies before they can destroy the planet. The action-packed episode is filled with dramatic moments, unexpected twists, and plenty of special effects.

As always, the episode is anchored by the dynamic performances of the lead actors, David Tennant as the Doctor and Catherine Tate as Donna. Their chemistry and rapport are on full display as they work together to save the world.

In addition to the exciting storyline, the episode also tackles some complex themes and ideas. It explores issues of power, control, and loyalty, as well as the ethical questions that arise when faced with difficult choices.

Overall, "The Poison Sky" is a thrilling episode of Doctor Who that delivers on all fronts. It is a must-see for fans of the series, and a great entry point for newcomers who may be unfamiliar with the show.