Charles Dickens’ father was once imprisoned for defaulting on a loan of 40 pounds, as host Laura Linney points out in her introduction to this splendid five-part Masterpiece presentation. The indelible experience helped inspire Little Dorrit, whose title character was raised in a notorious London debtors’ prison by a father incarcerated there for 25 years. This tale is brought to vivid life by screenwriter Andrew Davies (who also wrote the award-winning Masterpiece adaptation of Bleak House) and a fine cast that includes Matthew Macfayden (MI-5), Tom Courtenay, and Andy Serkis, who creates a villain as memorable as his Gollum in The Lord of the Rings. Newcomer Claire Foy plays the heroine of a story that’s just as relevant in today’s troubled economy as it was in Dickens’ day. Sundays, March 29–April 26, at 9 p.m., PBS