Idris, 46, starred as John Luther alongside Ruth, 36, as Alice for the first three seasons of the hit BBC detective drama.
However, viewers were left wandering what had happened to Alice at the end of season three as she was left for dead off-screen having faced off against Megan Cantor (Laura Haddock).
Ruth’s return to the drama has been confirmed ahead of the season premiere, however, viewers still don’t know what has happened to Alice in the mean time.
Fans should not worry as Idris has revealed viewers will learn what happened to Alice in her five-year break from the show.
We answer that in this season
Speaking ahead of the show’s return, Idris told press: “Last season, there was a little bit of being not sure what happened to her.”
The main component of season four saw Luther try to investigate Alice’s death, after the news she had died was announce minutes into the opening episode.
However, it was later revealed Alice and Luther had been in contact via a burner phone after she and the DCI having met up at the end of season three.
Idris continued: "I think I can say, safely, that we answer that in this season.”
Luther star Idris also went on to explain why there are such big gaps between each series, as the last season aired back in 2015.
He explained to Digital Spy: “Luther wouldn't work if we did it year-in, year-out, because it's very dark.”
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