During his time in the ED, Dylan has developed strong friendships with Zoe Hanna (Sunetra Sarker) and Lofty Chiltern (Lee Mead).

Dylan briefly takes up the position of acting clinical lead, and tries to improve standards in the ED, but he was challenged by the job's demands.

[citation needed] Actor William Beck joined the cast of Casualty as regular character Dylan Keogh during the twenty-fifth series.

[1] He was introduced as a replacement for fellow emergency medicine doctor Ruth Winters (Georgia Taylor), who had been admitted to a psychiatric unit in earlier episodes.

[3] Speaking to Sarah Ellis of Inside Soap, Beck told her that Dylan finds his work easier to deal with, as he prefers 'known quantities' to people who he deems unreliable.

[4] In the official press release for his arrival, Beck explained that in Dylan's fictional backstory he had ended up working as a general practitioner at a surgery in the countryside, despite being gifted at A&E medicine.

[1] Dylan was brought to the Emergency Department (ED) by Miriam Turner (Cheryl Campbell), who mentored him, along with clinical lead Nick Jordan (Michael French).

[13] Dylan later suggested that Lofty run the ED for the day, but it ended in tragedy when agency nurse Diane Stuart (Catherine Skinner) died.

Following the end of his first shift, Dylan called David "an odd fish", which made Elaine Reilly of What's on TV wonder if they would form a friendship.

[3] Beck told Lisa Williams of the Irish Independent that it was highly unlikely Sam and Dylan's marriage would work out, explaining, "if I say that we were married in Vegas, that gives you some idea of the longevity of the relationship".

He finds it hard to hide his real feelings for her when he's being questioned They lose all sense of professionalism, and end up bickering in the middle of the hearing room!

[19] Salt explained that when Sam receives the call to rescue a pair of trapped dog walkers, she needs someone else's help and the only doctor who could abseil was Dylan.

As they climbed into the hole to treat Amanda Franks (Connie Fisher) and David Hooper (Daymon Britton), all of Dylan and Sam's issues about their marriage came to a head.

[21] Nick Jordan (Michael French) notices their behaviour and tells Sam to find a way to work with Dylan, but she decides to return to the Army.

[24] In an interview with Digital Spy's Daniel Kilkelly, show producer Nikki Wilson told him that Amanda's appearance would trigger "an interesting" storyline arc for Dylan.

Producer Erika Hossington had teased the character's return in August 2014, saying that a "familiar face" would make a surprise reappearance in October that year.

[28] Beck told David Brown of the Radio Times that returning to the show felt "strange but yet very similar" and he relished the chance to play Dylan again, as he enjoyed the role.

Zoe and Caleb Knight (Richard Winsor) were struggling to cope with an influx of football fans who were injured during a fight, so Dylan got straight to work.

[16] Following Connie's sudden departure, Max Walker (Jamie Davis) suggested that Dylan should take up the position of acting clinical lead.

[30] Beck told Elaine Reilly of What's on TV that Dylan feels emotionally blackmailed by Zoe, after she says there will be benefits to the job, such as hiring and firing staff.

[32] As the character was shown to be suffering with psychological issues, producers introduced his estranged father, Brian Carroll (Matthew Marsh), in August 2015, leading to further exploration of his fictional background.

Beck told Laura Heffernan of Inside Soap that Dylan had not been in touch with his father for a long time, so when he was reunited with him he felt "paralysed by the situation".

[34] Stuart Cheetham, the show's story producer, wanted to challenge Dylan by giving him OCD, as he is deemed to be a very logical and rational person.

[36] In late October 2016, new F1 doctor Sebastian Grayling (Rik Makarem) joins the ED staff and immediately makes a bad impression when he hits Dylan's dog Dervla with his bike, causing her to run off.

As his first day goes on, Seb ignores the wishes of a dying patient, managing to "spark the wrath" of both Dylan and clinical lead Elle Gardner (Jaye Griffiths).

With Dylan facing suspension from the hospital, Max and Jez Andrews (Lloyd Everitt) try to record Seb admitting to making a false allegation, but their plan fails.

[41] At the start of series 32, Dylan is one of four characters, along with David, Louise Tyler (Azuka Oforka) and Alicia Munroe (Chelsea Halfpenny), who travel to Northern France to offer assistance at a refugee camp.

[43] Raffety stated, "It's the start of a dark, downward spiral for Dylan and this Sanosi story taps into a deep chasm in his soul, one of desperate loneliness – and one he will probably never admit.

[47] He was later nominated for Best Soap Actor (Male) at the 2018 Digital Spy Reader Awards; he came in joint ninth place with 3.9% of the total votes.

[5] David Butcher of Radio Times was a fan of the character, writing "Dylan is such a peculiar, grizzled, blinking, arrogant, uptight, tactless sociopath that it was hard to imagine him having a relationship with anything warmer than a stethoscope.