Despite its many deaths and bleak ending, Avengers: Infinity War has no shortage of jokes and light-hearted moments, like Thor (Chris Hemsworth) constantly referring to Rocket Raccoon (Bradley Cooper) as a "rabbit," Tony Stark (Robert Downey Jr.) calling Ebony Maw (Tom Vaughan-Lawlor) "Squidward," or Rocket asking Bucky (Sebastian Stan) for his metal arm in the middle of a Wakandan battlefield.
One meta joke that didn't make it into the film, however, would have poked fun at the fact that Benedict Cumberbatch and Robert Downey Jr. have both played a certain turn-of-the-century London-based detective. The Russos thought about including it during the scene when Doctor Strange opens a portal into Central Park to recruit Tony Stark while he walks with Pepper Potts (Gwyneth Paltrow), talking about having kids while she just wants to get married first.
This would have been a clear jab at Cumberbatch's role on the BBC series Sherlock, a modern take on the classic Holmesian stories of Sir Arthur Conan Doyle, created by Doctor Who alumni Mark Gatiss and Steven Moffat. Cumberbatch starred as the eccentric yet brilliant Sherlock Holmes, while Martin Freeman (another MCU resident) played Watson. In addition, Downey's portrayed Holmes alongside Jude Law's Watson in two well-received films by Guy Ritchie.
"It is also a very obvious joke. Not that we can't be accused of having made obvious jokes before," added the Russo sibling, probably hinting that the remark would have been too "Deadpool-y" to include in the final movie.
The Russo Brothers aren't above smart, self-aware comedy. After all, they really cut their directing teeth on shows such as Arrested Development and Community. It just seems that the "Sherlock" joke would have been too over-the-top for the general seriousness of Infinity War. Moreover, it had enough on its plate in uniting the entire Marvel Universe without needing to connect two Sherlock realities as well.
Fans can discover this piece of trivia and more on the film's commentary track when Avengers: Infinity War arrives on home video August 14.