Warning: Spoilers for Sicario: Day of the Soldado.

Sicario: Day of the Soldado may successfully make a franchise from the 2015 original, but it's missing one key element: Emily Blunt. For the most part, Sicario 2 is a worthy follow-up, not quite matching Denis Villeneuve's film but certainly not besmirching it, although audiences are sure to be questioning where the lead has gone.

Emily Blunt's Kate Mercer was the protagonist of the first Sicario, an FBI drug sting enforcer roped into an illicit inter-agency task force that played liberally with state, federal and international law in America's war on drugs. The film left her broken, used by the CIA's Matt Graver (Josh Brolin) to enable a hit on drug kingpin and threatened into silence by enforcer Alejandro (Benicio del Toro); the audience's view into this morally grey world, it left a bitter taste. In Sicario 2, however, she's not present or even mentioned.

This is doubly surprising as writer Taylor Sheridan initially said Blunt was going to play a part in the movie alongside Brolin and del Toro (who do return, both in beefed up parts thanks to their co-star's absence). However, he later backtracked, saying he couldn't find a way to make it work. Based on where he left Kate in Sicario 1, though, that's hardly surprising.

Why Emily Blunt's Absence Helped Sicario 2

Kate Mercer was a puppet, only on the team because the CIA needed an FBI agent to work on US soil; now the mission was over, her usefulness had ceased, and with her barely able to cope with what had happened, she was hardly an asset. Sicario 2 details a covert operation put together by Graver, and Blunt's character offers nothing logical to that sting.

Emily Blunt's absence does offer Day of the Soldado some fresh opportunities that Sheridan definitely uses to his advantage. Whereas the first Sicario was seeing this cynical in-between from an outsider's eyes, slowly revealing to the audience how the illicit war really operated, Sicario 2 flips it to start from the top and look down; we learn straight-up the extents that Matt Graver and his team are willing to go to, and so are instead watching the fallout as that cracks and becomes public. This culminates in the hard-lined Matt ending up seeing the emotional and personal cost of what he does when Alejandro is seemingly killed, a twisted mirror to Kate's arc. Putting Blunt into this story could distract from that.

Will Emily Blunt Be In Sicario 3?

That arc is also why Blunt should return for Sicario 3. We now have the two principals - Kate and Matt - on opposite trajectories: the brute has seen the light; the rule-abider has tasted the dark. The natural progression of Kate's arc is for her to begin to lose herself in this newly discovered world just as Matt flips. While Sicario 2 could exist without Emily Blunt and benefitted from her absence, the story set up here needs her.

And it may just happen. Multiple people involved with the Sicario franchise, including producer Trent Luckinbill, have said they would like to see Emily Blunt return in a likely Sicario 3. Given how tight the series has become on its characters as much as the gang war, it's the only right thing to do.

Next: You Can 'Absolutely' Expect Sicario 3 To Happen