Pearl Mackie has been announced as the new Doctor Who companion to Peter Capaldi's Time Lord.
The former Doctors actress joins a host of stars who found fame as The Time Lord's assistants.
The Doctor has been wandering around the universe for hundreds of years in BBC One's long-running sci-fi series. But he has also picked up a companion or two along the way.
Here is a selection of assistants who have shared the screen with The Time Lord over the years.
1. Clara Oswald
Played by Jenna Coleman, Clara is one of the Doctor's most extraordinary companions, she allowed the time winds to tear her into different iterations of herself.
These different Claras helped the Time Lord on many occasions, with one of them even persuading the first Doctor to steal the Tardis that became 'his' time machine.
Clara was present when the 11th Doctor (played by Matt Smith) regenerated into the 12th Doctor (Capaldi). At the end of series nine, Clara set off with Ashildr (Maisie Williams from Game Of Thrones) to explore the universe.
2. Sarah Jane Smith
Played by Elisabeth Sladen, investigative journalist Sarah Jane joined the show after stowing away on the Tardis. She accompanied the third Doctor (Jon Pertwee) and stayed with him after he regenerated into the fourth (Tom Baker).
More than 30 years after her debut, she returned to feature in her own spin-off show The Sarah Jane Adventures.
Sadly, Elisabeth died in April 2011 after a battle with cancer.
3. Rose Tyler
Played by Billie Piper, brave and feisty shop assistant Rose gave the former teen pop star turned actress a new credibility. Billie portrayed the first new companion when the show was revived in 2005.
She appeared opposite the ninth Doctor (Christopher Eccleston) for his one-series run and then opposite the 10th (David Tennant). Rose developed a very strong bond with the main character and kissed him at one stage.
4. Amy Pond
Played by Karen Gillan, Amy joined the show as a policewoman kissagram, although viewers also saw her as a small child when the Doctor visited her many years earlier.
Amy remained in the show for more than two series, much of it with her screen husband Rory (Arthur Darvill). Companion to the 11th Doctor (Matt Smith), she raised a few eyebrows with her selection of mini-skirts.
5. Susan Foreman
Played by Carol Ann Ford, she was the first ever companion. Teenager Susan was introduced as the granddaughter of the Doctor (William Hartnell).
She stayed in the show until she was locked out of the Tardis to allow her to slow down the pace of her life and spend time with a freedom fighter with whom she had fallen in love.
6. Donna Noble
Played by Catherine Tate, opinionated Donna helped to save civilisation from the Daleks during her spell with the 10th Doctor.
She had all memories of her adventures with the Doctor erased when she left his side. But she remains a fan favourite.
K-9 has been mainly voiced by John Leeson. The robotic dog with a laser nose made its first appearance alongside the fourth Doctor. Initially due to appear in one story, producers wisely decided to keep K-9.
There were three versions of K-9, each going on to stay with a different companion. K-9 made a reappearance with the 10th Doctor and also appeared in The Sarah Jane Adventures.
Played by Mary Tamm and Lalla Ward, it's a notable first as Romana became the first of the Doctor's companions to regenerate.
A fellow Time Lord, she was ordered to accompany the fourth Doctor to find the Keys Of Time. Lalla, the second actress to play Romana, married her co-star Tom Baker in real life.