When Alexandrou took over the role, Martin became part of the regular cast, and was featured in prominent storylines such as having sex with Sonia Fowler (Natalie Cassidy) and getting her pregnant with their daughter, Bex Fowler (Jade Sharif/Jasmine Armfield); developing a romantic crush on Zoe Slater (Michelle Ryan), which is not reciprocated, killing Sonia's former fiancé, Jamie Mitchell (Jack Ryder) after running him over in his car, which results in Martin being imprisoned for Jamie's death and subsequently feuding with Jamie's relative Phil Mitchell (Steve McFadden); enduring a problematic marriage with Sonia after their wedding; being stalked by Sarah Cairns (Alison Pargeter), and coping with the deaths of both his brother, Mark Fowler (Todd Carty) and mother Pauline Fowler (Wendy Richard).

Since his return in 2014, Martin has divorced Sonia; married Stacey Slater (Lacey Turner); finding out that Stacey's son Arthur Fowler is actually the son of his best friend Kush Kazemi (Davood Ghadami); surviving a bus crash; a brief two week stint in prison for assaulting a police officer, the premature birth of his daughter, Hope Fowler; briefly separating from Stacey after discovering her one-night stand with her former lover, Max Branning (Jake Wood); feuding with both Kush as well as Stacey's cousin, Kat Slater (Jessie Wallace) over Arthur’s custody; dealing with Bex's disappearance and attempted suicide; being blackmailed by Phil’s son, Ben Mitchell (Max Bowden) into committing crimes for him, ending his marriage to Stacey in attempts to protect her and their children against the death threats made towards them by Ben, a one-night stand with Stacey's best friend, Ruby Allen (Louisa Lytton), descending into crime, being involved in a hit-and-run accident, kidnapping Keanu Taylor (Danny Walters) and faking his death with help from Linda Carter (Kellie Bright), briefly reuniting with Sonia, a year-long marriage to Ruby, discovering that his stepdaughter, Lily Slater (Lillia Turner) is pregnant at the age of twelve, and learning that Ruby had secretly had his son, Roman Allen.

Sonia is feeling vulnerable after being dumped by Enrico di Clemente (Francis Pandolfo), and after getting drunk, they lose their virginities to each other; she becomes pregnant, but they are both completely unaware of the pregnancy until she goes into childbirth.

Once released, Martin resumes his criminal lifestyle by robbing a shop, blackmailing Kareena Ferreira (Pooja Shah) and growing cannabis in his late father's shed, assisted by his best friend, Asif Malik (Ashvin Luximon).

This leads to family friend Derek Harkinson (Ian Lavender) taking the blame when the police find out, as Martin cannot risk trouble with the law, due to his previous convictions.

After a few brief relationships, including a one-night stand with Kelly Taylor (Brooke Kinsella), Martin begins growing close to Sonia, and they fall in love.

After admitting that their affair is a lie, Sarah stabs Martin with a kitchen knife but Sonia hits her over the head with Pauline's fruit bowl.

In this time, she also attempted to sleep with Phil Mitchell (Steve McFadden) Martin returns to Walford to support Sonia on the evening of her Fat Blasters' Christmas party, but arrives late and discovers she has collapsed due to complications with a gastric band she got in Bulgaria.

He, Stacey Slater (Lacey Turner) and Kush Kazemi (Davood Ghadami) discover Nick's dead body at number 23 (recreating the first ever scene of EastEnders).

After agreeing not to speak of the matter, they discover that Nick's mother Dot Branning (June Brown) has called the police and confessed that she has killed him.

He later returns while Ian and his wife Jane Beale (Laurie Brett) are on their honeymoon, staying at their house and catches Cindy Williams (Mimi Keene) having sex with Liam Butcher (James Forde) and decides to keep an eye on her.

Stacey is electrocuted by a faulty socket that Lee Carter (Danny Hatchard) failed to repair properly so Martin punches him and threatens to kill him if the baby dies as a result.

Shakil's friend Keegan Baker (Zack Morris) takes revenge by distributing a pornographic clip with Bex's face imposed on the model's body, which Martin eventually discovers.

While Martin is in prison, Stacey discovers that Arthur is at high risk of having Brugada's Syndrome, a heart condition inherited from Kush.

However, Stacey says that if they do not talk, their relationship cannot survive, so she admits to having sex with Max, later explaining that she did so as she and Martin never have time for themselves and she is left to manage the house.

Martin refuses to talk to Stacey about it so it does not ruin Christmas for their children and that he will not accept blame for her actions, saying she should leave if it is going to destroy their family.

A dejected Martin ends up spending New Year's Eve alone in his house and the next day, confronts Max about sleeping with Stacey but declines to punch him, saying revenge doesn't help.

In June 2019, Martin is angry when Kush decides that he wants to file for joint custody over Arthur, causing the end of their friendship, though they later make amends.

He decides to stay and pleads with Phil's son Ben Mitchell (Max Bowden) to let Stacey return to Walford.

In December 2019, Martin and Ben's associate Charlie "Tubbs" Savage (Tayla Kovacevic-Ebong), knock someone over on their way from a dodgy dealing, before driving off.

In September 2020, Martin is attacked and left for dead by Vinny Panesar (Shiv Jalota) when he stages a robbery to help Ruby claim an insurance.

He is manipulated Into believing Stacey caused a fall when she had nothing to do with it leading to her being falsely imprisoned for 6 months and he is made to neglect his children and Kush dies during this time.

In August 2022, Lily steals pills that Denise Fox (Diane Parish) had confiscated from Jada Lennox (Kelsey Calladine-Smith).

However, Martin struggles to accept Stacey posting explicit photos of herself on SecretCam, an OnlyFans-style website, for money, and they choose to remain friends.

Their blossoming romance is interrupted by her daughter, Avani Nandra-Hart (Aaliyah James) who wants Priya and her father, Ravi Gulati (Aaron Thiara) to reunite.

Sharon and Phil hire Johnny Carter (Charlie Suff) to trace Ruby, and they find her living in Essex with their son Roman Allen.

[1] The storyline was used to spread a public message on the increased risk of genetic defects in late pregnancies, with Pauline undergoing amniocentesis tests.

It was initially reported that Martin would remain on the show until August 2007, however the character departed in February 2007 to tie in with his wife Sonia Fowler's (Natalie Cassidy) exit.

[6] He also said, "Our casting executive Julia Crampsie has found a genuine relatable London bloke in the talented James Bye—we are sure that viewers old and new will soon warm to Martin Fowler's charms as he returns home to Walford.

[7] In 2020, Sara Wallis and Ian Hyland from The Daily Mirror placed Martin 56th on their ranked list of the best EastEnders characters of all time, calling him Pauline and Arthur's teenage "tearaway son".