He originally came to Walford - a fictional borough in East London - in 2003 as a new member of the Watts family who had a difficult past and rough childhood, though his identity was unknown for almost thirty years.

The follow-up of Den's comeback saw him and Dennis compete against each other in a longstanding conflict that eventually came to an end in 2005 when Den was ultimately killed off on the show's twentieth anniversary episode dated 18 February 2005; Dennis later discovered his father's fate on 29 August 2005, the same day he finally married his adopted sister Sharon (Letitia Dean) after the couple managed to repair their once-forbidden romance.

During his time on the show, Dennis established an intense feud with his alpha-male rival and the square's undisputed top-dog kingpin Phil Mitchell (Steve McFadden) - also Sharon's on-off boyfriend.

He also bonded with his and Sharon's half-sister Vicki Fowler (Scarlett Alice Johnson); formed a mutual friendship with Dalton's right-hand mobster Andy Hunter (Michael Higgs); embarked on an initial relationship with his brief girlfriend Zoe Slater (Michelle Ryan); developed a warm companionship with local gossip Dot Cotton (June Brown); slept with his acquaintance Kate Morton (Jill Halfpenny) during her marriage prospects with Phil; instituted major interactions with Sharon's family friend Pauline Fowler (Wendy Richard) along with fellow neighbour Pat Harris (Pam St Clement) and Zoe's surrogate father Charlie (Derek Martin); temporarily clashed with Phil's brother Grant (Ross Kemp) over the latter's previous marriage with Sharon; and later teamed up with the Mitchell brothers, along with their mother Peggy Mitchell (Barbara Windsor) and cousin Billy (Perry Fenwick), to help their family bring Sharon's stepmother Chrissie (Tracy-Ann Oberman) to justice for killing Den and framing Peggy's daughter Sam (Kim Medcalf) for his murder.

In his exit storyline towards the climax of 2005, Dennis became enemies with the square's reigning crime lord Johnny Allen (Billy Murray).

This came to an unfortunate end when Dennis brutally attacked Johnny for threatening him and throttling Sharon into leaving Walford, as well as killing Andy on the night Den died earlier on.

The character of Dennis Rickman quickly became established as the show's leading man and a "soap sex-symbol",[1] with Harman noted for his "dark good looks" and "fantastic" physique.

It is gradually revealed that he was neglected as a child by his mother and abused by a succession of her boyfriends, ultimately spending some time living in a children's home.

The rivalry with Phil is concluded by Den himself when he returns from Spain in September 2003, confirming the theory which Dennis had uncovered two months earlier.

However, Andy's death was believed to have been suicide at the time, which buys Johnny an extra year of freedom - as Dennis will find out to his cost.

She is desperate to get pregnant for real and resorts to sleeping with Den, who had told her to feign the pregnancy in his own attempt to split Sharon from Dennis.

Dennis has his doubts about Chrissie's story that Den had left her a few months before in favour of another woman, but drops the matter to spare Sharon's feelings.

Dennis and Sharon go on to marry soon afterwards, and following this, they learn that Sam Mitchell had exhumed their father's body from his grave in the cellar of The Queen Victoria public house.

Den then regained consciousness and grabbed Chrissie, who delivered a fatal blow, but left Zoe to believe she had killed him.

The three women then buried his body in the basement, with Chrissie being able to avoid suspicion for the next few months by inventing a story that Den had left her for another woman.

On Christmas Day 2005, Sharon is admitted to hospital with suspected food poisoning, but finds out she is pregnant, despite the previous belief that she was infertile following an abortion 10 years earlier.

After cleaning his hands of Johnny's blood, Dennis makes his way towards the Albert Square gardens, where the locals are setting up fireworks ready to welcome in 2006.

However, over five years later, on Christmas Day 2019, they end up splitting, after Phil discovers that Sharon had an affair with his daughter's fiancé, Keanu Taylor (Danny Walters).

Denny is among the passengers on the boat, and, although everyone else survives the crash, he consequently loses his life after suffering a cardiac arrest from drowning in the ensuing carnage.

Dennis Rickman was created by the show's producers as the hardman successor to the character of Steve Owen, who had bowed out during the previous year.

EastEnders executive producer Louise Berridge noted: "We cast Nigel for his tremendous acting ability and his screen presence, but there's no question he's also a very sexy young man."

[7] During his time on the show, Dennis often butted heads with various alpha-males, including hardman Phil Mitchell (Steve McFadden) and crime boss Johnny Allen (Billy Murray), but was friends with mobster Andy Hunter (Michael Higgs) and developed a warm relationship with local gossip, Dot Cotton (June Brown).

The representation of Dennis as "smouldering thug"[10] was apparent from his first appearance in Walford, when he hit resident top dog Phil Mitchell.

[12] The character of Dennis Rickman quickly became established as the show's leading man and a "soap sex-symbol",[13] with Harman noted for his "dark good looks" and "fantastic" physique.

In 2020, Sara Wallis and Ian Hyland from The Daily Mirror placed Dennis 58th on their ranked list of the best EastEnders characters of all time, calling him a "bed-hopping criminal" who was "a chip off the old block" from his father.