One of the biggest mysteries leading into Guardians of the Galaxy Vol. 2 is the identity of Star-Lord's (Chris Pratt) father. Many have speculated that new cast member Kurt Russell is playing this new character, but even if that were true, we don't know anything about his identity. Writer-director James Gunn shared a new hand-drawn storyboard sketch from a scene shot earlier today, which teases the mystery behind Peter Quill's dad.

Last week, James Gunn started a new tradition from the set known as #‎WhatWeShotWednesday‬, where he shares one mysterious sketch from a scene they shot that day. Unfortunately, the sketches themselves are quite messy, and it's tough to glean any specific story details from these drawings. Today's sketch features three characters standing around... something, with a line of dialogue from Star-Lord that reads "My Mom always told me my Dad was from the stars."

All we know about Star-Lord's dad is that it won't be the same person from the Marvel Comics, J'son. While many have speculated that Kurt Russell is playing Star-Lord's dad, there could be another possibility as well. Earlier this month, Sylvester Stallone was spotted leaving the same hotel as the Guardians of the Galaxy Vol. 2 cast members, holding a script in hand, leading many to assume he has a secret role in the superhero sequel. Another report surfaced just a few days later, claiming that the actor is wearing a costume that resembles his iconic Judge Dredd costume from the 1995 movie. Is it possible that Sylvester Stallone is Quill's actually pops?

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The original Guardians, including Chris Pratt (Jurassic World, Guardians of the Galaxy) as Peter Quill/Star-Lord; Zoe Saldana (Guardians of the Galaxy, Star Trek Into Darkness) as Gamora; Dave Bautista (Spectre, Guardians of the Galaxy) as Drax; Vin Diesel (Guardians of the Galaxy, Furious 7) as the voice of Groot; Bradley Cooper (Joy, American Sniper) as the voice of Rocket are set to return. Other returning Guardians of the Galaxy stars include Michael Rooker (Guardians of the Galaxy, Jumper) as Yondu; Karen Gillan (Guardians of the Galaxy, The Big Short) as Nebula; and Sean Gunn (Guardians of the Galaxy, Gilmore Girls) as Kraglin. Unfortunately, we recently learned that another iconic character from the original movie will not be returning, with Benicio Del Toro recently confirming he will not be back as The Collector.

Marvel has set a May 5, 2017 release date for Guardians of the Galaxy Vol. 2, which will ensure that the studio kicks off the summer movie season for the second year in a row. This year's lucrative summer season gets started in just over a month when Captain America: Civil War hits theaters on May 6. Do you have any theories about what James Gunn's #WhatWeShotWednesday sketch could mean? Chime in with your thoughts below, and stay tuned for more on Guardians of the Galaxy Vol. 2.