On a train crossing from Switzerland to Germany, an old man was searched by customs officials. They found 9,000 euros in cash. Their suspicions started a journey back in time, to a hoard of art hidden since the Third Reich. It has reignited passions that seemed long spent.

These were not old masters but new - works the Nazis labelled 'degenerate', like the Jews themselves. They tried to wipe out both. The father of the old man on the train was a dealer for the Nazis, selling these works abroad and keeping some for himself. In a two-part special, imagine... follows both his story and those of the families who have been fighting to find their lost art.

imagine... tells how the end of the war was only the beginning of another battle. In the art world in Germany, it was business as usual. Many people in museums, galleries and auction houses in Germany remained in their positions when the war was over. So people involved in looting art might now be in charge of deciding whether to return it. For families, often living in exile, it was an uphill struggle. For them the discovery of the Gurlitt hoard has raised new hopes - and repeated some old disappointments.

For five decades the woman they call The Divine Miss M has forged a path which has taken her from a pineapple canning factory in Honolulu to becoming a Hollywood legend. Alan Yentob joins Bette Midler on a journey through the chorus lines of Broadway, the bathhouses and nightclubs of the 1970s, to the very top of the film industry. Her combination of a soulful voice and the raucous wit of Mae West has made her name as an outrageous, but always captivating, all-round entertainer.

There is no-one quite like Anselm Kiefer. Having achieved fame and notoriety in equal measure in the 1980s, he has become one of the world's most singular and successful artists. Working with themes of history, memory and mythology, Kiefer produces work that is consistently controversial, and monumental in its scale and ambition.

In this imagine... Alan Yentob joins the artist at his studios in France and Germany as he prepares for a retrospective at the Royal Academy. In a series of frank interviews set against the backdrop of his awe-inspiring studios, Kiefer discusses the impact of his most significant pieces, installs a selection of new work, and explains why he is as excited and driven by his practice now, at the age of 69, as he was when he began.

In a revealing documentary, Mike Leigh, director of Secrets & Lies, Vera Drake and Abigail's Party among many others, talks to Alan Yentob about a unique body of work and a lifelong struggle to make films on his own terms.

On day one of a Mike Leigh film, there is no script, no story and the actors do not know if they will even be in the final film. It is a process that has yielded some of cinema's most celebrated performances, and Leigh's new film Mr Turner is already winning critical acclaim.

Actors including Jim Broadbent, Eddie Marsan, Sally Hawkins, Lesley Manville and James Corden give fascinating insights into the director and his distinctive method of working.

In this thoughtful, lyrical film, Imagine talks to the acclaimed and curiously divided Irish writer Colm Toibin. Loud and affable in person, Toibin writes sombre stories of grief and quiet heartbreak, repeatedly returning to the dark narrative of his own childhood and the complicated relationships between mothers and sons.

In the year that his bestselling novel Brooklyn is being adapted for the cinema and The Testament of Mary continues to provoke controversy, Toibin publishes his most poignant and personal novel yet.

With Fiona Shaw, Anne Enright and Nick Hornby.