I’ll split this into 2 bios for convenience: Music bio and Writing bio.

Music Bio

Darran Brennan (aka Tilersun and formerly EDM producer, Demon Groove) is a singer-songwriter and music producer from Dublin, Ireland.

In 2009 I started making dubstep under the name Groove Demon. I changed the name to Demon Groove because I thought Groove Demon sounded too much like a DJ, I saw myself as a producer, and the name was already taken. In September 2011 I signed my EP to Frederik Olufsen’s label (of the Bang and Olufsen family), Royal Fetish Recordings under the moniker Demon Groove. Between 2011 and 2015 I released eleven EDM face mashers
through the coolest indie labels around, including Adapted Records and Tasty Records.

Serving up bangers lost its appeal when the EDM (Electronic Dance Music) scene devolved into fan-service for teenage boys playing video games and mollied-up ravers who put their hands up for anything remotely energetic. Determined to remain authentic as an artist, (yeser, EDM has [had] depth), I went travelling for 6 months. I crossed the Swizz Alps by bike and lived for 3 months on a remote Thai Island. During this time I wrote songs on a ukulele each night on my balcony.

After gigging around Dublin and some busking on th city streets, many new songs began to formulate. I was less drawn to connecting with music fans sonically and it became about the lyrics. Deeply, I felt the music that resonated the most with me had powerful stories within the structure of the songs.

Completly subconsciously, I employed a fall-and-catch idea when writing lyrics, something I developed thorough writing novels, which entails taking the listener to one place, making them assume something sociologically or politically (or both) and then taking it to somewhere else less chaotic. This is my natural being; a problem solver and a mediator. I want the listener to return to a grounded place of common sense, harmony and peace—that’s what all great music should do!

The innocent vibe that arrived (or returned) through travelling developed, more profoundly, its layers by playing the songs live around Dublin. The pandemic threw the proverbial spanner in the works, however, just as I was reaching a level of comfort in front of a live audience, which wasn’t helped by writing three novels, which I have obsessed over editing. I finally finished 2 of them in 2023 (I say
that but…)

I also make music for TV and Film under Inertia Productions and chill-out music under Intoya (pronounced into-ya)



To the point of self-annihilation, I have become obsessed with writing stories. Paradoxically, I’ve never been happier. I’ve been writing for over a decade and novels (relentlessly) for seven years—in search of an authentic, unpretentious, concise and clever story/voice.

I’m from Dublin, Ireland and began writing seriously in 2015 after I spent six months cycling through Europe and living on a Thai island. I used that life-affirming experience to shape the narrative and character arcs of my latest book  about self-love, learning to be free and brave and following your wildest dreams. Since 2015 I have written 11 complete manuscripts and hundreds of short stories. I self-published my debut novel TREOIR: CURSE ON THE ISLAND in 2021.


2015, during a summer biking from Dublin to Milan and living on the Thai island of Koh Chang, I wrote a blog that I turned into a travel memoir called in Fields of Nettles). While on Koh Chang, I began writing a story about a band travelling on a small aircraft that crashes and the fallout after the singer dies. I had no idea how to structure sentences properly, I vaguely understood what an independent clause was, and my spelling was horrendous—I still struggle with whether it’s an ‘e’ or an ‘a’. However, I am becoming a bit of a grammar-Nazi and a logophile.

During my three months on the island, I began scribbling a first draft of ‘a book then called, ‘The Governor’s Daughter’). It’s the story of an American man trying to reconnect with his estranged ex-con son. A son who wants to prove himself to a group of militant patriots. When the father finds the runaway daughter of a corrupt governor, he sees it as a way for them to bond.



When I returned to Dublin at the start of 2016, I began editing ‘The Governor’s Daughter’. This is when my obsession with the craft of writing really dugs  its hooks into my soul. I taught myself the intimacies of voice and what it means to be a proper writer by reading and experimenting—you might be able to see that in my early short stories.

An 80,000-word edited draft of ‘The Governor’s Daughter’ was finally put aside early 2017, and I wrote two 60,000-word manuscripts—which served as lessons in structuring a book. I did the same thing in 2018, finishing two 80,000-word manuscripts: ‘The True King of Ireland‘ (about a dolphin that helps a politician win an election) and ‘Pieces of a Man’ (about a divorcee writing a book on a plane and falling in love with an air stewardess). As decent as they were, I felt I hadn’t nailed it yet. Sensing the real books were to come, I shelved both. (I may return to them at a later date).


In 2019, after working without much enthusiasm at a job that I had lost my passion for, I was fired by an ego maniac of an employer and fell into a depression. This turned out to be serendipitous. From the ashes of despair, a novel came: ‘Treoir’. Around that time, I was having lucid dreams. I’m not usually one of those people who tries to interpret dreams, but this one, in particular, resonated with me. I was on an island helping kids escape from crazed people. It was simple but visceral and stayed with me all that day. I decided to write it down. That dream became the island setting for ‘Treoir(Irish for  Guardian), and the children became the subjects of the novel: Jonah, a genius with albinism, and the protagonist’s precocious niece, Quinn. I wrote the first draft of ‘Treoir’ in about 6 weeks, between May-June 2019, and after several rewrites and months of intensive editing, I self-published it on October 9th,  2020.

While editing ‘Treoir’, I began writing a book I called Death of Venice (not called that now). I wanted to explore having an antagonist as the narrator and further the theme I began with ‘Treoir’ of how need and human nature conspire sometimes to turn good people bad.

In it a stressed-out barrister finds his once-perfect marriage turning abusive and falls for a beautiful, intoxicating sex worker—ignoring the
the fact he’s worked his entire life to become a judge.

I didn’t want to write a legal thriller per se (I’m not a lawyer) but I did want to write about the corruption of a character who wears a cape (and a wig in this instance). Given how small Ireland is, I’m curious if a barrister or judge would dare create such a corrupt view of the Irish legal profession as I have.



I got lost in those stories— and loved every second (even at the constant risk of developing deep-vein thrombosis). Writing for 10 hours per day wasn’t, and isn’t anything unusual for me. Between 2019-2020 I also wrote several manuscripts (each one over the course of 2 months). One is about a streetwise Dublin barber who tries to escape his miserable past by helping a young hood put his life back together after his father kills himself.

Another was a semi-autobiographical, satirical, dark-comedy based around a failed musician facing reality again and trying to figure himself out and what it is to love.

I also wrote a book about Irish twins born months apart who get themselves mixed up in political activism that leads to a twisted, Hitchcockian plot involving fake identities and manipulating people into murdering for them, potentially a 4th instalment of a trilogy I have written). 

I wrote half-a-book about two bored high fliers who make a bet and play with a loner’s life, inviting him into their celebrity world, to see if he can be corrupted, and if so, how far he can be pushed: murder being the ultimate, prize scooping act.

While writing those books, I was taking days and weekends to edit ‘Treoir’. I decided I wasn’t comfortable with seeking an agent and publisher as I didn’t fully understand the industry. Having what I believed a great story in ‘Treoir’, I decided to try self-publishing. I also thought I might be able to design my own cover as I have a love of design and Photoshop. My attempts at a cover:

After another two rounds with beta readers, I went back to full-time editing ‘Treoir’, around December 2019, and after more months of intensive work, I had the first solid version of ‘Treoir: Curse on the Island’ by the end of May 2020. Then, during the summer of 2020, I used the Covid lockdowns to perfect the novel, obsessing over every piece of syntax, reading the day’s work aloud, recording it, listening to it before bed, waking and listening again, correcting every comma, every clunky word, until I felt I was seeing a movie play in my head.

Besides all that—while recording music in between—I was learning all about self-publishing.

The Final Cover

Post Self-Publication and a New Trilogy.

My newest book is about the ephemeral love that forms between a suicidal young woman and a dying man after she offers to donate her heart to him.

This is the book I think I was trying to write when I began writing. Consequently, two of the other books had a thread throughout: metamorphosis. At the heart of those stories is an innocence and a desire to do good, and stopping that happening are outside influences, which the protagonists must figure out before tackling whatever obstacle is in their way.

When writing those books, the themes weren’t always clear, and hence the books are a (now highly refined) exploration into, and meditation on, what was getting in the way of the characters figuring themselves out. Those three books were not written as a trilogy but they had a similar character at the centre, who would go to become Nelly in all three books.

A few months after the second edit of the first of that trilogy it became obvious that one of my books was an origins story about Nelly’s parents. Another felt like the epilogue in a trilogy. The child in one is the moral compass for her parents when they spiral into destruction. I felt that her confusion stemmed from lies her parents told her. I just had to connect the dots.

Each of the three books had to go through extensive, laborious rewrites to make them one cohesive story. But I feel like I’ve created an inspiring character who goes from suicidal loner to hero over the 3 books. I want her to be an inspiration not only to young women but to men as the story is about discovering your self-worth and power.


I’m inspired by writers like John Steinbeck, Emily Brontë, Alexander Dumas, George Orwell, Jane Austin, Robert M. Pirsig and Salman Rushdie among many others.