A photo hint on the day by Murray Gold gave "most of" the cast list (Jan 18):
And a photo from the recording session by BBC radio publicist Reetu Kabra (available on the David Tennant fan site) confirmed the lead casting.
The play will broadcast on BBC Radio 3, probably in a slot of their Sunday evening "Drama on 3" series (8 pm, UK time).
Twitter hints and guesses at the moment seem to indicate an air date somewhere between mid-April to early May. (April 17-May 8?) It will be available worldwide on iPlayer. Judging from the site layout, BBC3 shows appear to be available "on demand" for 7 days.
Murray's quote from Twitter (Jan 21):
Emerald O Hanrahan and David Tennant squished hearts and made tragic pie in the Kafka musical today.
