In 2005, American producer Laura Starecheski visited the largest state psychiatric care institution in New York City to learn about the art produced by the patients. As Documentary on One ( RTÉ Radio 1, 2pm) reveals, she stumbled upon a mystery that took almost 10 years to unravel.
Co Kildare singer- songwriter and musician Inni- K hitches a ride on the Mystery Train with John Kelly ( RTÉ Lyric FM, 7pm) and gets a chance to pick the music.
Historian Philippe Sands looks into the disappearance of senior Nazi politician Otto Waechter in Intrigue: The Ratline ( BBC Radio 4, 1.45pm) and in the process uncovers a story of a son battling with the sins of the father.
Jack Rooke profiles controversial rapper and activist MIA in Mamma MIA: Influence of an Icon ( BBC Radio 4, 11.30am).
Acclaimed novelist Ian Rankin ( above) joins Jo Whiley & Simon Mayo ( BBC Radio 2, 5pm) to chat about his book In A House Of Lies.
Marty Whelan is enjoying a Roman holiday live on Marty in the Morning ( RTÉ Lyric FM, 7am). He’s in the Eternal City to see a production of The Magic Flute, and he’ll be going behind the scenes at the atmospheric Teatro dell’Opera di Roma.
Sue Limb’s comedy Gloomsbury
( BBC Radio 4, 11.30am) is back for a new series as Henry ( Jonathan Coy) tries to ignore his 50th birthday. However, Vera ( Miriam Margolyes) has other ideas.