[2] Lucas is introduced as a reformed drug addict and criminal-turned-preacher who appears as the estranged father of established character Chelsea Fox (Tiana Benjamin/Zaraah Abrahams).

He also has a young son, Jordan (Michael-Joel Stuart), and later goes on to marry Chelsea's mother Denise (Diane Parish) - whom he had previously been in a relationship with prior to their reunion.

While the character originally appeared to be respectfully dedicated to his own religious convictions, Lucas slowly became the show's secondary antagonist when he causes the death of his former wife Trina (Sharon Duncan Brewster) by leaving her to die in a raking accident; murders Denise's ex-husband Owen Turner (Lee Ross) on their wedding day; drowning his son's dog Sugar after the latter risks unearthing Owen's corpse; and strangling Denise before locking her up in a basement while allowing her family to believe that she is responsible for the murders - with Lucas killing another woman to use as Denise's supposed body so that her family could believe that she committed suicide.

Lucas made a previously unannounced reappearance on 1 January 2016 before returning for a short stint in the year, in which he escaped prison until he was rearrested and left the programme again on 10 March 2016.

Lucas Johnson first appears on Albert Square when his estranged daughter, Chelsea Fox (Tiana Benjamin), tracks him down to a community service - whereupon she discovers that he is a preacher.

Chelsea reluctantly agrees to give Lucas a chance, but is unhappy to learn he has a son, Jordan (Michael-Joel David Stuart).

Denise's ex-husband, Owen Turner (Lee Ross), suspects Lucas was involved in Trina's death and confronts him on his wedding day.

When Jordan's sheepdog, Sugar, starts sniffing around the tree, Lucas disposes of her at a nearby canal, telling his family that she ran away.

He meets a woman named Jade (Niamh Webb) in a bar and takes her to a secluded area, where he forces her to kneel and pray.

Lucas murders a prostitute, Gemma Charleston (Rita Balogun), who resembles Denise, and places her body in the canal.

Six years later, after discovering Jordan has been in trouble with the police, Denise tells her daughter Libby Fox (Belinda Owusu) that she is going to visit Lucas in prison.

Lucas tells Denise that he has taken all responsibilities for his past actions, as he has been mentally ill and wanted to believe he was being guided by some spiritual being.

Denise later finds Jordan (now played by Joivan Wade) and convinces him and his son JJ Johnson (Zayden Kareem) to move in with her.

Lucas returns to Walford after being released from prison on Christmas Day 2020, having reunited with his daughter Chelsea (now Zaraah Abrahams).

A week later, Lucas returns to the square and starts stalking Denise as he watches her with her boyfriend Jack Branning (Scott Maslen).

After calling the police, Jack finds Lucas walking around the square and chases after him, with Callum Highway (Tony Clay) in tow.

Denise is later found kidnapped by an unknown assailant, who is later revealed to be Caleb Malone (Ben Freeman), putting Lucas in the clear.

Having experienced guilt over assaulting Nish Panesar (Navin Chowdhry) with a champagne bottle and covering up the murder of Keanu Taylor (Danny Walters).

Gilet's casting in the show was announced in January 2008, when the character was described as "attractive, charismatic, strong and forthright" and "just a dodgy geezer with a murky past.

Entertainment website Digital Spy reported: "Trina arrives and surprises Lucas and she makes it very clear she wants to give things another go.

Gilet explained that although Lucas does not want people dead and has no malice in his heart, he sees killing as a way to stop things from happening.

[9] When the show's executive producer Diederick Santer was asked by Digital Spy what was lined up for Lucas in 2010, he said "He's got right on his side, hasn't he?

"[10] Gilet described Lucas as having "Jekyll and Hyde" aspects to his character, and tries to hide the darker side of his personality from Denise.

Gilet commented: "Every actor enjoys playing a character who's flawed – but how long can Lucas continue to hide the dark side of himself before the cracks start to show?

"[11] Gilet has called Lucas "a very good character to play because of his complexity", explaining: "I think that's partly because he's a guy who always strives to do the right thing but his path for doing that gets warped as time goes on.

[14] In June 2010, a decision was made to reshoot scenes planned months in advance involving Lucas picking up a sex worker named Jade (Niamh Webb) who he seemingly strangles after forcing her to pray for God's forgiveness.

[16] Speaking of his return to the serial, Gilet stated: "I'm thrilled and honoured to be asked to breathe life once again into such a complex, controversial and diverse character but, most importantly to have another opportunity to work alongside one of UK's finest actors, Diane Parish.

[18] The BBC received 103 complaints from viewers after it was hinted that Lucas had killed Sugar the dog, compared to "a handful" following his murders of Trina and Owen.

The BBC responded saying they do not condone the killing of dogs or people, but iterated that the behaviour was in keeping with the character, adding that "no animals were harmed in the making of this story.

[20] In January 2011, Gilet was nominated for Serial Drama Performance at the 2011 National Television Awards for his portrayal of Lucas but did not make it through to the shortlist.