It’s only June, but the PR strategy for Blake Lively’s mysterious new movie, A Simple Favor, has already reached its “cheeky social media interaction” stage. Exhibit A: Lively posted a new poster of the film on Instagram featuring herself and costar Anna Kendrick in which they both pose with martinis and generally look like ‘50s-era housewives. (Is A Simple Favor really about the intricacies behind a disappearance or two women lending each other Bombay Sapphire for cocktails? Hmm. Think about it.)

As she’s been doing lately on Instagram, Lively accompanied the photo with an irreverent caption. Only this time, it’s about Kendrick and not her hubby, Ryan Reynolds. Or is it? “@annakendrick47 is the hotter, female(r) version of my husband...so, would it reaaaally count as cheating??” she wrote.

But then, of course, the follow-up comments just kept rolling in. “So glad we’re finally taking this public,” Kendrick responded a few hours later. “I let Ryan have Deadpool, he can give me this.” And to complete the commenting trifecta, Reynolds soon jumped in with the following: “The most ambitious crossover event in history. I’ll miss you both. Tell my story.”

This playful social media back-and-forth is hardly the first Instagram stunt that Lively has pulled in honor of her upcoming film. Last month, she shocked her loyal 'gram followers by deleting all photos from her account and unfollowing everyone (including her husband) save for a handful of women named Emily Nelson, which also happens to be the name of her character in A Simple Favor. She also ominously changed her bio to read, "What happened to Emily?...." Spooky.

If you’re out of the loop on Lively and Kendrick’s upcoming film, it looks quite suspenseful from the one trailer that was released—Lively plays a glamorous entrepreneur who befriends Kendrick’s small-town mommy blogger, only to disappear after the women begin to form a close bond. Whether she was murdered or just has a secret to bury, well, you can find out on September 14.

Related: Blake Lively's Deadpool 2 Premiere Look Took a 'Bus Full of People' to Achieve