There's sad news for Doctor Who fans as Amy and Rory Pond are leaving the hit show.
They joined Matt Smith as the Doctor in his first adventure last year, and will be leaving in a heartbreaking storyline during the next series.
Doctor Who boss Steven Moffat revealed the Doctor was going to meet "a new friend" but didn't say who.
Matt Smith said: "It's very disappointing, but this show is about change and regeneration."
We asked you who should play Doctor Who's new companion.
"I think the Doctor's new companion should be Billie Piper again."
Cameron, 11, Devon, England
"I think the companion should be someone funny like a comedian because it would make Doctor Who funnier."
Mia, 10, Greater Manchester, England
"I liked Amy so much, she was the greatest companion. Maybe they should have Ed Sheeran or Emma Watson, that would be good!"
Holly, 12, Gloucester, England
"I think Selena Gomez because she is well known and it will be a twist."
Tally, 13, Dover, England
"I think Stacey Solomon should be Doctor Who's new companion as she is a great role model."
Chloe and Henry, 7, Lancashire, England
"I think that the Doctor should get Rose back, she has always been his favourite companion. Or maybe Donna, Catherine Tate is so funny."
Emily, 12, Skipton, England
"It's a shame that Amy is leaving. I think that the Doctor needs a man to be his companion, maybe Johnny Depp."
Thanisha, 11, London, England
"I think that Dani Harmer should be the next companion because she is funny and would make a good friend."
Tom, 10, Cambridge, England
"I will really miss Amy and Rory. They were amazing and the best companion's the Doctor has had. I think the new companion should be called Marissa Maxwell and the actress should be Taylor Swift."
Poppy, 11, Wirral, England
"Amy was a great companion but her story had finished. I hope the next companion is an alien from a different planet."
Leighton, 14, London, England
"I will miss Amy and Rory lots but I think that someone funny like Miranda Hart, James Corden or Noel Fielding would be a good companion."
Olivia, 13, Staffordshire, England
"I think the Doctor needs someone feisty and sassy. Someone like Sarah Jane or someone like Lady Catrina in David Tennant's Easter special."
Sophie, 14, Norfolk, England
"I hope they have another Scottish person because it was nice to see someone Scottish on my TV for a change."
Isabel, 13, Aberdeen, Scotland
"I'm really sad about Amy leaving, no one can replace her. What about Selena Gomez."
Markie, 9, Wales
"I think Katherine Kelly should become Doctor Who's new companion."
Eleanor, 11, Carlisle, England
"I will really miss Amy but I think Kristen Stewart should be the next Amy."
Sarah, 12, Birmingham, England
"I think the Doctor's next companion should be Morgan from Merlin."
Mohsan, 9, West Yorkshire, England
"I think Miranda Hart should be the next companion. It would make it really funny!"
Tammy, 13, Devon, England
"I think that the new companion should be a boy. They always seem to have girls and I think the show would seem more adventurous if a strong, fast and clever man would step beside the Doctor as his companion. Maybe someone from the Sarah Jane Adventures."
Reese, 12, Birmingham, England
"I think Doctor Who needs a lazy or quiet person who is more intelligent than him. Or another Time Lord with him, that would be so cool!"
Nazifa, 11, London, England
"I am so sad, Amy and Rory were the best companion's ever! I hope the new companion will be called Amber and will be really shy but is amazing at karate!"
Hannah, 10, Chester, England
"I can't believe that they are leaving. I think Jack should come back and maybe have Esther and Rex from Torchwood with him."
Claire, 14, West Midlands, England
"I think the new companion should be either Dani Harmer or Lacey Turner."
Matthew, 11, Lancaster, England
"Bring back Rose...even though she is in a parallel world."
Luke, 10, Scotland
"I think Amy did a really good job on Doctor Who and that she should be replaced by Lady Gaga."
Baden, 10, Derbyshire, England
"I think the Doctor needs someone that has already been in Doctor Who. Someone that's funny and will always look after him, someone like John Barrowman."
Lauren, 13, Devon, England
"I think James Corden because the Doctor and him are very good friends."
Luke, 10, Greater Manchester, England
"Dani Harmer has to be the one!"
Nathan, 11, West Yorkshire, England
"I think that the Doctor should find someone that can laugh easily and be helpful most of the time, but also be quite clumsy with a little bit of a temper so that there would be more drama between them."
Lizzy, 12, West Midlands, England
"I would like to be the Doctor's assistant because I know lots about Doctor Who."
Ellie, 8, South Wales
"I think that the companion should be called Rachael! I'm going to miss Amy but I can't wait to watch the next episodes."
Rachael, 10, West Yorkshire, England
"I'm a big Doctor Who fan. I think the new companion should be funny, a bit mad, adventurous, happy, cool and a bit geeky."
Maeve, 9, Belfast, Northern Ireland
"I'm going to miss Amy and Rory. They were some of the funniest and best companions ever! I hope the next companion is called Emmy and she is energetic!"
Louise, 12, Ireland
"I will miss Amy very much. I hope the new companion is just as good. Hopefully they'll pick a man for a change. Maybe James Corden?"
Charlotte, 13, Coventry, England
"I think the new companion should be a girl and somebody who can stand on her own two feet!"
Jessica, 9 Nottingham, England
"Someone who is feisty and trusts the Doctor, but also questions him a lot."
Hassaanah, 12, London, England
"I think that it is sad that Amy is leaving the Doctor, but I am looking forward to finding out who the next companion is!"
Sophie, 9, Harrogate, England
"I think the Doctor should find someone and fall in love."
Isabel, 9, Watford, England
"I can't believe that Amy is leaving! No one can replace her, that's how special she is."
Sidhra, 13, Birmingham, England
"I think that Dani Harmer (Tracy Beaker) would make a great companion for the Doctor. Young people can relate to her and it would be a great step into adult television!"
Natasha, 11, West Wickham, England
"They should start a competition and let a fan win the part of the companion. I hope they do something exiting because I am starting to get bored with Doctor Who."
Adham, 12, Gloucestershire, England
"Amy has been in it for a long time, I think she should have a change."
Benjamin, 9, Elgin, Scotland
"I will miss Amy, she has been one of the best companions."
Lauren, 17, Tyne and Wear, England
"I think the Doctor needs somebody who understands him and makes him laugh. He needs a helpful person who likes going on adventures."
Lisa, 11, London, England