‘The Bletchley Circle’ spinoff is in the works

U.S. streaming service BritBox is getting into original programming, ordering “The Bletchley Circle: San Francisco,” a spinoff of popular UK period drama “The Bletchley Circle.”

BritBox is run by BBC Worldwide, the commercial arm of pubcaster BBC, and British commercial net ITV. It rolled out in the U.S. last year with a lineup of British shows for U.S. consumers.

The original “The Bletchley Circle” series followed a group of four female codebreakers at the famous World War II code-breaking center Bletchley Park, who went on to use their skills to investigate a series of complex crimes.

“The Bletchley Circle: San Francisco” will be on BritBox – and ITV in the U.K. – later this year. It will follow two of the original lead characters, Millie (Rachel Stirling) and Jean (Julie Graham), as they travel to 1956 America and join forces with two U.S. codebreakers to tackle a string of murder cases.

The series is formatted as four stories, each of which unfolds over two episodes.