TRIVIA

Gemma Chan said in a interview that she and the other synths in the series had to go through a synth school.

Silas Capek is a reference to Karel Capek, writer of the play R.U.R (Rossum's Universal Robots). He also created the term robot from the Czech word "robota", which means "work".

The seven word activation phrase used to put new synths into setup mode [ep 1] is homage to the 2001 film A.I. in which a robot child is designed to love unconditionally and imprints onto whomever activates him with a seven word phrase.

On the Persona Synthetics website, Sally is listed as a model PS Lundstrom S6-XI. Lars Lundström is the creator of the TV series "Äkta människor" of which "Humans" is an adaptation.

William Hurt was also in A.I. Artificial Intelligence (2001) which he played the creator of androids which serve humans.

Gemma Chan, Tom Goodman Hill, Danny Webb and Colin Morgan have all appeared in Doctor Who.

Series 1 episode 4 features a house-party. The music in the background is a remix of the theme tune from the tv series Utopia (2013). The two series share a composer, Cristobal Tapia de Veer. The two series also share several crew and cast, including actors, episode writers/producers/directors, special effects, camera crew, etc.

Gemma Chan and Katharine Parkinson both have appeared in the TV series Sherlock.

Gemma Chan who plays Anita/Mia also played a character called Mia in Doctor Who (2005) The Waters Of Mars.

Gemma Chan and Katherine Parkinson appeared in the TV sitcom The IT Crowd.

In episode 3, when Geoge asks Vera to clear his downstairs room, a box for a vintage Pelham Puppet toy can be seen in shot. The Synths are, of course, the ultimate puppet.

In her best-known TV series, The IT Crowd, Katherine Parkinson plays a character who is placed in a position of authority over a computer department, despite her lack of knowledge about and dislike of computers. Likewise, in Humans, Parkinson's character is unwillingly placed in a position of authority over a computerized synthetic person, despite her lack of knowledge about and dislike of synths.

Gemma Chan acted in one episode of The IT Crowd (2006), a show starring Katherine Parkinson.

Katherine Parkinson (Laura Hawkins), Jill Halfpenny (Jill Drummond) and Will Tudor (Odi) have worked together on the TV series 'In the Club'. They played Kim, Diane and Jack respectively.

Katherine Parkinson (Laura Hawkins) and Jonathan Aris (Robert) both have starred in the TV series 'Sherlock'. They played Kitty Riley and Anderson respectively.

Colin Morgan (Leo) has worked with both real-life husband and wife, Harry Peacock and Katherine Parkinson in different projects. He worked with Harry in the TV series 'The Living and the Dead', where they played Nathan Appleby and Smith respectively, while in 'Humans' he worked with Katherine and they appear as Leo and Laura Hawkins respectively.

Tom Goodman-Hill (Joe Hawkins), Rebecca Front (Vera) and Colin Morgan (Leo) have all worked with actor Bradley James in one project or another. Tom and Rebecca and Bradley have all appeared together in an episode of the TV series 'Lewis' (which was the sole episode Bradley appeared in). They starred as Richard Helm, Ch. Supt. Innocent and Jack Roth respectively; Colin worked with Bradley in the TV series 'Merlin'. They played Merlin and King Arthur respectively.

Sope Dirisu (Fred) and Colin Morgan (Leo) have starred together in the film 'The Huntsman: Winter's War'. They played Tull and the Duke of Blackwood respectively.

Colin Morgan (Leo), Danny Webb (Hobb) and Jill Halfpenny (Jill Drummond) have all worked with actor Michael Byrne in one project or another. Colin worked with him in 'The Living and the Dead' as Ebenezer Alsop and Nathan Appleby respectively. Danny and Jill worked with him in 'Lightfields' as Pip Felwood, Barry Felwood and Martha Felwood respectively.

Katherine Parkinson and Emily Berrington performed together on stage in "Dead Funny" at London's Vaudeville theatre during 2016.

Danny Webb (Hobb) and Jill Halfpenny (Jill Drummond) both appeared in the TV mini-series 'Lightfields'. They played Barry Felwood and Martha Felwood respectively.

SPOILERS

The trivia items below may give away important plot points. The inscription in the book says "Primum Non Nocere" - "First Do No Harm"; which is the the principal concept of bioethics/healthcare, but can be interpreted as the First Law of Robotic "A robot may not injure a human being or, through inaction, allow a human being to come to harm."

Niska (Emily Berrington) keeps a book called "The Ghost in the Machine."