[4][5] Sheridan started writing music and playing guitar while living in New York City, and in 2004 Ryan moved to Glasgow to form the rockband Shiversaint.

When Whitehead saw them playing a cover of Little Lion Man by Mumford and Sons in Grafton Street, he stopped and listened for ten minutes before he dropped his card in Sheridan's guitar case.

Whitehead nominated Sheridan's song Machine for the SupaJam competition to win the opportunity to play at the Festival Internacional de Benicàssim in Spain.

Support acts were singer/songwriter Sara Lou and Consumer Love Affair, with a guest performance by Crowded House bass guitarist Nick Seymour and Tomas Cosinski on guitar.

Halfway through the concert Graczyk switched from playing cajon to drums and bass guitarist Neil Dorrington joined the band.

On 25 November 2011, Ryan released a four-track Christmas EP Walking in the Air, with all profits from the sales of the single being donated to Make-A-Wish Ireland.

Sheridan's song Take It All Back from The Day You Live Forever featured on Raw (TV series) season 4, episode 1 on RTÉ One.

In March Ryan appeared on Bernard Dunne's RTÉ Bród Club performing The Day You Live Forever as gaeilge.

[18] On 20 April, Sheridan was presented with a platinum plaque for his debut album, The Day You Live Forever,[19] at his sold-out show in The Olympia Theatre, Dublin.

[20] Later on 27 September, Sheridan played a headline performance at The Palace Nightclub on Camden Street in Dublin as part of their Arthur's Day Celebrations.

As special guest to Rea Garvey in January and February followed by appearances with Silly in May, he performed to approximately 60,000 people in a matter of months.

[23] On 4 May, Sheridan announced that cajon player Artur Graczyk had decided to permanently leave the band and would be replaced by Jimmy Rainsford.

[25] The Day You Live Forever Tour continued in 2014, beginning at The Capitol in Mannheim on 15 February and finishing at The Postbahnhof, Berlin on 2 March.