The Doctor (Matt Smith) receives a call from the Indian Space Agency about a spaceship that will crash into Earth in six hours. It will be destroyed by missiles unless the Doctor stops it first. He takes along Queen Nefertiti of Egypt (Diann Steele), big game hunter John Riddell (Rupert Graves), companions Amy (Karen Gillan) and Rory (Arthur Darvill) and accidentally Rory’s father Brian (Mark Williams). Amy discovers that the ship is a Silurian ark to carry the reptilian humanoids to a new planet, along with ancient Earth species doomed by an imminent cometary impact.

There are no Silurians aboard, but there are dinosaurs. After being attacked by Pteranodons, the Doctor, Rory, and Brian are escorted by two robots to a dangerous man named Solomon (David Bradley), who is injured by Raptors. He is actually a black-market trader who raided the ship to steal the dinosaurs, using his robots to kill all the Silurians. He is unable to control the ship, which is now about to crash on Earth. He decides to kidnap Queen Nefertiti, who agrees to go with him to save the others, but the ship is still targeted by missiles.

The Doctor rides a Triceratops, Amy and Rory shoot dinosaurs with tranquilizer guns. The Doctor disables the robots and saves Nefertiti. They manage to get the missiles to target Solomon’s ship and it blows up. They Silurian ship is sent away from Earth. Everyone returns home and Brian starts an intergalactic touring business. Nefertiti goes off with John Riddell.

The episode was created, not only to showcase the dinosaurs, which are a great improvement over those in Jon Pertwee’s Invasion of the Dinosaurs in 1974, but as a rollicking adventure with the motley crew of characters that could only appear in Doctor Who. Rupert Graves is known to us from 12 Monkeys, Sherlock, V for Vendetta, and the Forsyte Saga. David Bradley played Argus Filch in the Harry Potter films and William Hartnell in various Doctor Who stories. Mark Williams played Arthur Weasley.

Nefertiti was chosen because no-one knows what happened to her. The sets were about the biggest ever made for Doctor Who. A preview at the 2012 San Diego Comic-Con was a great hit. The episode was generally praised as great fun and enormously entertaining. Matt Smith had to wear padded trousers to ride the Triceratops but loved it. The Raptors were from the series Primeval. The character of John Riddell was based on Allan Quatermain created by H. Rider Haggard.