This Broadchurch and Doctor Who fixture plays Crowley, the ne'er-do-well demon in our mismatched duo. And creator Gaiman can recall the exact moment he knew that he'd be casting Tennant in the role. "I just remember the moment where I was halfway through writing Episode 3," the author told Radio Times at Amazon’s European showcase. "Suddenly I had an idea for a scene which involves some physical comedy, and I thought, 'I don't know who could pull that off? That's really difficult.' And suddenly I thought: 'David Tennant could pull that off.' And suddenly the way that I wrote Crowley from that moment changed. And I was absolutely certain and determined that David would be my Crowley."

The other half in the show's central pair is Masters of Sex alum Michael Sheen, who portrays the angel Aziraphale. Though according to the same Radio Times interview, he initially thought he was being asked to play Crowley. "I sent [Sheen] the scripts and said, 'Can we meet for dinner?'" Gaiman recalled. "We met for dinner, he started saying — 'I've read the scripts, I don't really think that I'd be a good fit for Crowley. I'm not really sure that I can see myself as him.' And I said, 'Yeah, well, I want you as Aziraphale.' He was like: 'What?'"

The actor who brought Don Draper to life has gotten the chance to flex his comedic muscles since Mad Men ended. In addition to his role of Richard Wayne Gary Wayne in Unbreakable Kimmy Schmidt, he's appeared in Random Acts of Flyness and Wet Hot American Summer: First Day of Camp, among others. And while Hamm plays the archangel Gabriel in Good Omens, he seems neither celestial or omniscient.

This young actor was previously in Medici and The Death and Life of John F. Donovan. Here, Buck plays the young antichrist, Adam, who seems very reluctant to fulfill his destiny.

Although she starred in the short-lived Emerald City series on NBC, Adria Arjona is still a relatively unknown actor. Here, she plays Anathema Device — a descendant of the witch Agnes Nutter, who wrote Nife and Accurate Prophecies of Agnes Nutter. The above preview for her character teases that not only is Anathema a Ph.D., bicyclist, and witch, but she's memorized all of her ancestor's prophesies, and is now trying to stop the end of the world from happening — "as one does."

Whitehall is a well-known comedian in the UK and starred in comedy shows Bad Education and Psychobitches — both opposite the Chilling Adventures of Sabrina star Michelle Gomez. Furthermore, he's done several Netflix specials and also has a docuseries called Jack Whitehall: Travels with My Father, in which the two men globe-trot together. But in Good Omens, Whitehall plays a witchfinder named Newton Pulsifer.

Who else but two-time Oscar-winner Frances McDormand could play the voice of God in Good Omens? While it's unclear whether we'll see her character onscreen or not, her voice will be a welcome inclusion in the show.

He's voiced Smaug in The Hobbit and played both Sherlock Holmes and Dr. Strange, so naturally, Cumberbatch's next career move is to play Satan himself.

Since Parks & Recreation went off the air in 2015, Offerman hasn't made many TV appearances. Fortunately for those of us who ascribe to the Swanson Pyramid of Greatness, however, the Making It co-host plays Good Omens character Thaddeus Dowling, who is the father of Warlock Dowling — aka the child originally mistaken to be the antichrist, per TVLine. "There may not be anyone alive who can deadpan a line quite as well as Nick Offerman," Gaiman said in a statement, per the article. "He's a terrific performer, and has to say a lot of things in Good Omens that are humanly impossible to deliver with a straight face. Fortunately, Nick is not entirely human."

Known for playing roles like Mycroft Holmes in Sherlock and Lord Marlborough in 2018's critical darling, The Favourite, Gatiss plays a Good Omens character named Mr. Harmony.

Richardson's Good Omens character, Madame Tracy, is described in the above Facebook video as a "kindly courtesan and medium" who is both "tolerant" and "a touchstone for what's good in humanity." The video teases that Madame Tracy will "find herself the first recorded case of Angelic Possession." Previously, Richardson has appeared in everything from The Young Victoria to the Harry Potter series, in which she played professional busybody Rita Skeeter.

Mr. Spinal Tap himself, the eponymous actor has been in everything from Laverne & Shirley to the more recent Better Call Saul. Here, McKean plays Shadwell, a character who is the last sergeant in the Witchfinder Army, according to the above video.

Fans of The Killing or Shonda Rhimes's short-lived drama The Catch will be happy to see Enos appear as a character named War.

The Enchanted April actor will appear in a small but important role as Agnes Nutter herself. "I played [Agnes] in the radio version [of Good Omens] and really enjoyed it. That's when I first got to know Neil [Gaiman]," Lawrence told Radio Times. "Later, I got a message from him saying, 'I am writing the TV script for Good Omens. I have put that "Agnes Nutter looks not unlike the actress Josie Lawrence."'

Lawrence was rehearsing the play Mother Courage at the same time, but Gaiman and crew were able to accommodate her schedule. "I got up very early one day, got burnt at the stake and went back to play Mother Courage," Lawrence told the outlet.

Cox has most recently been in the 2018 HBO show Succession, but the actor has been in everything from Troy to Deadwood. Here, he brings his perpetually stern face to Good Omens, where, naturally, he plays Death itself.

When Good Omens drops on Amazon, fans will be able to watch the cast shine in all of their "very strange and wonderful" glory, to quote Gaiman himself.