When Doctor Who returned to TV screens in 2005, longtime fans were excited to get the time-traveling alien hero back. Viewers were introduced to new companions, enemies and allies, many of whom were played by familiar faces. Some were already well-known, while others were just beginning their roads to stardom.

Many of the Doctor’s companions went on to be Avengers, Legends and supervillains, with a few enemies winning Oscars and Tonys. When we look back now, it’s fun to see many of our favorites making surprise appearances with everyone’s favorite Time Lord. Fire up the TARDIS, these are 10 stars you forgot appeared on Doctor Who. 

GUGU MBATHA-RAW

One of the fun parts of the new series is seeing The Doctor figure out how to interact with companions’ families. Things got particularly tense with Martha’s mom. However, her sister Tish, played by Gugu Mbatha-Raw, was friendly with the Tenth Doctor, because she saw how much Martha liked him.

Since helping Martha and The Doctor defeat The Master in season three, Mbatha-Raw’s career has taken off with award-winning performances in Belle and Beyond the Lights, as well as the Black Mirror episode “San Junipero.” She’s also rumored to be one of the many actresses in the running for the role of Catwoman in The Batman.

CHRIS NOTH

Season 11 saw the show undergo many changes, including a new cast, new head writer and just an overall new tone. To help smooth over the debuts, several familiar faces guest starred throughout the season.

One of the most surprising was Law & Order star Chris Noth as obnoxious businessman/possible politician Jack Robertson. He was a real creep who had giant spiders nesting under his new hotel. Noth’s horrible character was clearly based on a famous figure, making him uncomfortably real to watch.

SOPHIE OKONEDO

During Matt Smith’s time as the Eleventh Doctor he had a fun group of allies, who recurred to help him fight the Silence. His travels into the future introduced him to Sophie Okonedo as Liz 10, the Queen ruling over Starship UK.

Liz 10 was a cool action hero Queen, sneaking around the ship to investigate the mystery hiding in plain sight. The Doctor has a long history with England’s monarchs, something Liz is very aware of, as his reputation precedes him. We’re still waiting to see the Thirteenth Doctor run into Liz again.

ALAN CUMMING

Whovians got an unexpected surprise when Alan Cumming guest starred in season 11’s “The Witchfinders.” The popular actor played King James, who was visiting a village to rid it of witches. Of course, there were no witches, just evil aliens.

In the span of 47 minutes, Cumming was menacing, vulnerable and funny. He had great chemistry with Tosin Cole’s Ryan as they bonded over missing lost loved ones. We wouldn’t be shocked if the fam finds a reason to cross paths with King James again.

OLIVIA COLMAN

The Eleventh Doctor’s first adventure was a non-stop race against time, as he tried to unmask Prisoner Zero, and stop the Earth from being destroyed. During his final confrontation with the alien criminal, it took on the guise of a comatose mother, played by Olivia Colman.

Colman was known for her supporting role in the film Hot Fuzz, and appearances on TV shows like Midsomer Murders and The Office. The scene is so great, because Colman looks non-threatening, but clearly Prisoner Zero is ready to let the world burn rather than go back to jail. It’s one of the most memorable moments from season five.

CAREY MULLIGAN

Every season including David Tennant has an episode that The Doctor wasn’t heavily featured in. These episodes required someone very good to carry them, and none worked better than “Blink.” Carey Mulligan’s Sally Sparrow was the first character to go up against the Weeping Angels.

She started the hour as a normal young woman, visiting her friend, while trying to figure out her life. As things progress, she jumps to shock, disbelief, acceptance, then fighting back. Considering the amazing work Mulligan regularly delivers now, this is a nice preview of showing how good she’s going to be.

SIMON PEGG

Coming back in 2005 was a big risk for Doctor Who. It helped that season one saw familiar faces guest star. In the episode “The Long Game” fan favorite Simon Pegg played The Editor. As The Editor, Pegg was working for the alien Jagrafess, who like all the others wanted to take over the world.

In addition to being known for Star Trek and Hot Fuzz, it’s no secret that Pegg is a big nerd, so seeing him on Doctor Who wasn’t a big surprise. This episode gets bonus points for also featuring Black Lightning’s Christine Adams and Shaun of the Dead’s Tamsin Greig. 

IAN MCKELLEN

The Great Intelligence doesn’t have a physical form, so it takes over the mind and body of its servants. When the Eleventh Doctor came up against the Great Intelligence, we knew someone with gravitas had to provide the voice. The show certainly delivered with Sir Ian McKellen.

With the help of its servant Dr. Simeon, played by Richard E. Grant, the Intelligence planned to use the frozen body of a mean nanny to take over the world. The Doctor managed to stop the Intelligence, but their confrontation seemingly served as a prequel to one of the creature’s previous appearances.

ANDREW GARFIELD

What makes Andrew Garfield’s appearance on Doctor Who so great isn’t that he helps The Doctor beat the Daleks, it’s the spectacularly bad southern accent he uses. In “Daleks in Manhattan” and its second part “Evolution of the Daleks,” Garfield plays Frank, a young man living in Hooverville during the Great Depression.

While The Doctor takes on the Daleks, Frank teams up with Martha to stop their plan. Though his character doesn’t have much to do, Garfield makes it a memorable appearance. This is one of the future Spider-Man’s earliest roles and you can see his enthusiasm on screen.

JAMES CORDEN

When the Eleventh Doctor moved in with Craig to investigate something weird in his apartment building, he finally had a good old fashioned mate. James Corden was Craig in “The Lodger” and “Closing Time,” letting Matt Smith show off his comedic skills.

Craig was jealous at first, but who wouldn’t be? Corden and Smith turned out to be a fantastic comedy duo, giving us a perfect blend of awkwardness and slapstick physical comedy. Since Corden is a little busy with his successful late night talk show, we don’t think we’ll see Craig again anytime soon, but we’d love to see his reaction now that The Doctor is a woman.