Mark Drakeford, Scott Quinnell & Dame Sian Phillips embark on an emotional journey in new TV series

Slam Media is proud to announce the return of the critically acclaimed series and winner of RTS Cymru Best Factual Entertainment programme 2025, Cyfrinachau’r Llyfrgell (Best Kept Secrets) for a second four-part series, airing on S4C and available on BBC iPlayer from September 16th 2025.

Following the success of Series 1, the new series once again takes Welsh celebrities on a deeply personal and emotional journey through the vaults of the National Library of Wales in Aberystwyth. This unique format blends genealogy, archive exploration, and personal storytelling, uncovering remarkable truths and long-forgotten secrets from family histories.

This season features a compelling line-up of well-known Welsh figures including former Welsh First Minister Mark Drakeford, legendary actress Dame Siân Phillips, Rugby Union and Rugby League icon Scott Quinnell and acclaimed author Caryl Lewis.

Hosted by BBC Radio Wales presenter Dot Davies, each one-hour episode invites audiences to share in a journey filled with emotion, revelation, and personal connection.

The first episode sees Mark Drakeford, Wales’ First Minister who led the people of Wales through the pandemic, handing over his personal papers to the Welsh Political Archive at the library.

The team of experts explain his place in the pantheon of Welsh political figures by showing him key moments in the nation’s history.

Viewers are also treated to Mark doing a dance move as he reflects on his grandmother performing a jig to celebrate Lloyd George giving the pension.

Mark, who admits he’s “been a member of Glamorgan Cricket Club longer than I’ve been a member of the Labour Party” is also presented with documents relating to the family farm which inspired his bardic name ‘Mark Pengwern’ and learns more about his personal hero, Jim Griffiths, the first Secretary of State for Wales.

Reflecting on his experience at the library, Mark admits, “Whenever I visit I get the feeling that I’m in a special place, a place where very important things are safely kept…

“But this is the first time I’ve seen so many treasures. That has really struck me. It’s incredible.”

Geraint Rhys Lewis, Executive Producer at Slam Media, said:

“Following the incredible reaction to the first series of Cyfrinachau’r Llyfrgell, we’re proud to announce that series 2 promises to be bigger and better again.

“Our home-made format is now a familiar concept, making it easier to entice big name celebrities to take part even though they still don’t know what’s ahead of them!

“S4Cs continued faith in the project and the National Library team’s buy-in to our populist approach to historical storytelling means we’ve really come up trumps this time with a wonderful variety of stories, surprises and secrets which sums up the unique magic of the National Library of Wales  – so eloquently described by Caryl Lewis in the final programme as, “Home to our identity, the pieces here are part of us, they define who and what we are as a nation.”