'Stargirl': One of The CW's last remaining superhero shows going full murder mystery for Season 3

Who needs friends or enemies when you can just swing your cosmic staff and have frenemies? “Frenemies” is literally the name of the game that’s afoot as Season 3 of DC’s Stargirl kicks off this week, with The CW embarking on 13 fatal episodes that balance the goodness in the bad guys against the badness in the JSA’s good guys — all wrapped up, believe it or not, in a new murder mystery whodunnit that’s set to span the whole season.

Explaining that the official “Frenemies” tagline was staked out by series creator and showrunner Geoff Johns, star Brec Bassinger (Courtney Whitmore aka Stargirl) recently told Entertainment Weekly that the new season’s tone may feel lighter as Courtney comes to embrace “what it means to be a superhero” by “[f]inding harmony between the good and the bad.” But, she added, the murder mystery at the series’ heart this fall is deadly serious…and seriously sneaky.

Who’s the victim — and, more importantly as the season progresses — who’s the perpetrating villain? “It will shock you. You will not see it coming,” teased Bassinger. “I think I was one of the only ones — I think it was maybe three people on set who knew the ending, me being one of them, and every person I've talked to when they read the script, or the editors when they watched the first cut, they were all shocked. At different times of the season, you'll think it's different people — and every time you'll be wrong. The ending will shock you.”

If that sounds like the ultimate superhero game of Clue, the whole “Frenemies” twist is designed to only deepen this season’s murder mystery. “Tone-wise, our showrunner Geoff wants each season to be totally different, which you saw between season 1 and season 2, and for season 3,” said Bassinger, “he knew he wanted the supervillains and heroes living in a town in harmony.”

That could make sussing out the real killer extra tricky, especially now that Sylvester Pemberton (aka Starman, played by Joel McHale) has taken up residence in the basement of the Whitmore-Dugan house and has a friendly claim of his own for command of the Cosmic Staff. Will the tension put Stargirl off her game? Bassinger said Sylvester’s methods may seem sly, but his heart’s definitely in the right place.

“Who does the Staff belong to? Why is he back?” Bassinger pondered. “Did he come back to take the Staff? I had those questions as an actor and then Courtney had those same questions as well. Even though she's worried, she does look up to him, even seeing him as a father figure, so it is a positive thing having him back. It's made pretty clear from the beginning what his true intentions are with coming back.”

That still doesn’t get viewers any closer, at least on day one, to sniffing out the killer walking among their newly close-knit community of heroes and villains. With Starman now a series regular and Obsidian (aka Green Lantern’s son, played by cast newcomer Tim Gabriel) joining the JSA’s ranks, Season 3 of DC’s Stargirl is set to go full Sherlock when it premieres at 8 p.m. ET at The CW on Wednesday, Aug. 31.

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