It was by no coincidence David Tennant and Michael Sheen were picked for the leading roles as the demon and the angel. The show follows the pair as they work together to try and stop the impending end of the world. Director of Good Omens Douglas Mackinnon has spoken exclusively to Express.co.uk about casting for the series on BBC Two and Amazon Prime.
The director has worked on other series including Dr Who and Sherlock and already had a close connection with Tennant before the casting for Good Omens.
Mackinnon said: “I knew David very well and Neil (Gaiman) knew Michael Sheen. It was like they were right [for the roles].
“With all casting it’s down to availability and the desire to do it.
“Even with the smaller cameos the commitment was brief but intense.”
Good Omens: David Tennant and Michael Sheen
But were Tennant and Sheen always destined to play the leading characters?
Mackinnon explained how Terry Gilliam, former member of the Monty Python comedy crew, actually had the rights to make a film version of the series.
He said the leading roles could have been very different in the film version.
Mackinnon said: “Robin Williams and Johnny Depp were going to play the two parts and we can see how that could work.
“Terry had the rights for about 10 years and he was quite close to making a film.”
By 2002 Gilliam had still hoped to make the film with its completed script, but by 2006 it seemed to have come to nothing.
In January 2017 it was announced Amazon Prime Video had given a green-light to a television series adaptation of the novel to be co-produced with the BBC.
Gaiman and Pratchett worked together to write the series and choose the cast.
Mackinnon said it was clear Tennant and Sheen were the perfect partners.
Piers Morgan shuts down Emily Thornberry over Labour tax row [TV ROW]
Laurence Fox hits out at Lily Allen on being told 'stick to acting' [TV ROW]
Caprice's husband can’t keep hands off her amid Dancing on Ice curse [FAN DISCUSSION]
He said: “About 10 minutes into the read through we saw the chemistry between them and it was just magical.
“[The chemistry] was just infectious and we had a fantastic time making it.”
Other huge names were also keen to get on board with the show alongside Tennant and Sheen.
Jon Hamm was cast as Archangel Gabriel and responded to the crew’s invitation in the best way.
Mackinnon said: “Jon Hamm was a big fan of the book and he just replied to the email about the role with two words - ‘yes’ and ‘Hamm’.”