Richard Eyre is to direct the film, which will air on the BBC in the United Kingdom and via Amazon Prime Video in the United States and Germany next year.
Hopkins will play the titular monarch and Thompson will play his oldest daughter Goneril. This marks the third time the pair will work together, following the period movies The Remains of the Day and Howards End.
Emily Watson will play Lear's middle daughter Regan and Florence Pugh will play the youngest sibling Cordelia. Rounding out the cast will be Jim Broadbent, Andrew Scott, John Macmillan, Jim Carter, Christopher Eccleston and Tobias Menzies.
"It is a tribute to the great Richard Eyre that we have brought together such a remarkable cast. The film is a testament to the BBC's on-going commitment to the single drama, and we are very appreciative of their continued support," executive producers Colin Callender and Sonia Friedman said in a joint statement Thursday.