PASADENA, Calif. (AP) — Benedict Cumberbatch had a ready answer when asked when he might star in another "Sherlock" on PBS.

"Goodbye," he said, pleasantly, as he quickly stepped off-camera during a satellite Q&A Wednesday.

Cumberbatch was speaking to TV critics from London about a very different drama he stars in and produced, "The Child in Time." The TV movie, based on Ian McEwan's novel about a couple whose child is kidnapped, co-stars Kelly Macdonald and debuts April 1 on public TV stations.

Macdonald, who'd flown in from her native Glasgow, Scotland, to promote the TV film, said she'd confessed to Cumberbatch that she was "a huge" fan of his modern-day Sherlock.

Macdonald has her own date with the sleuth, playing his housekeeper in an upcoming big-screen comedy starring Will Ferrell.