Warner Bros.

Sherlock Holmes' next case won't be closed until 2021.

Warner Bros. has pushed back "Sherlock Holmes 3," which reunites stars Robert Downey Jr. and Jude Law, a year from its original Christmas 2020 release date.

That means the third movie in the detective franchise will come a decade after "Sherlock Holmes: A Game of Shadows."

The first "Sherlock Holmes" opened in 2009, with Guy Ritchie directing Downey as the famous sleuth and Law as his sidekick Dr. Watson.

Both it and the sequel were big hits, but the third movie has been stuck in a development swirl as there was no script. Now, writer Chris Brancato (co-creator, "Narcos") has been hired, so things should move more quickly.

It's unknown if Ritchie will return to direct. His next film, the live-action remake of "Aladdin," opens May 19.

The new date means "Sherlock Holmes" will face the second weekend of "Avatar 3," the adaptation of Broadway's "Wicked," and an untitled live-action Disney film.