The fictional National Treasure is said to have been inspired by the Jimmy Savile and Rolf Harris cases.
The producers described it as a “timely exploration of truth, memory, trust and family”.
The Harry Potter and Cracker actor plays Paul Finchley, one half of a comedy double act whose life starts to unravel when faced with allegations from the 1990s.
Julie Waters is Marie, his wife of more than 40 years, who is forced to ask herself if Finchley is the man she thought he was when they married.
The four-part drama also stars Andrea Riseborough, who played the title role in Margaret Thatcher: The Long Walk to Finchley, as their daughter Dee, an addict whose recovery is threatened by her father’s arrest and trial.
National Treasure was written by Jack Thorne, who also penned the This is England series for Channel 4. Filming starts next month and it will be screened later this year.
Co-executive producer George Faber said: “Our drama tackles the complex relationship between celebrity, sex and power and it needed Britain’s finest acting talent to do it justice.
“It’s the quality of Jack Thorne’s script that’s attracted such a stellar cast.”