"A Martian, two villains and a young lady walk into a bar in National City... " Although it sounds like the setup for a Comic-Con-inspired joke, it's actually the latest casting news from Supergirl's panel Saturday, July 22. Fans not only learned more about the emerging threat from DC Worldkiller Reign (Odette Annable), but were introduced to a few more characters poised to cross paths with Supergirl in Season 3. The CW also released the first Supergirl Season 3 trailer, which you can see below descriptions of these new characters.

Adrian Pasdar (Heroes, Colony, Marvel's Agents of S.H.I.E.L.D.) will play the charismatic capitalist Morgan Edge, a ruthless real estate developer who will stop at nothing to get what he wants (and what he feels he deserves). The DC villain has big plans for National City, which instantly put him at odds with Supergirl (Melissa Benoist) and Lena Luthor (Katie McGrath). You can get your first look at this villain in the trailer below, courtesy of The CW Network YouTube. Carl Lumbly (Alias, Southland, The Cure for Wellness) embodies the classic DC character M'yrnn J'onzz, the father of J'onn J'onnz, the Martian Manhunter (David Harewood). A pacifist religious leader on Mars, M'yrn pushes his son in unexpected ways. Actor Lumbly is no stranger to the J'onzz family, as he's voiced the Martian Manhunter on the Justice League animated series.

Yael Grobglas (Jane the Virgin, Reign) portrays DC character Psi, a psychic villain who uses people's own minds against them. Psi's agenda puts her on Supergirl's radar, and their meeting will affect the Girl of Steel in surprising ways. Emma Tremblay (Elysium, The Judge, The Giver, Wayward Pines) plays Ruby, a smart, independently minded National City kid who's fascinated by Supergirl and ends up in jeopardy because of it.

Earlier this month, we reported that Smallville alum Erica Durance has signed on to portray the new Alura Zor-El, taking over for Laura Benanti, who had to depart the role due to her obligations on Broadway. Supergirl Season 3 will pick up after Kara Zor-El rid National City of Queen Rhea and her Daxamite army. While this was certainly a major win for Supergirl, it was also one that came at a significant cost, as Kara was forced to sacrifice her budding relationship with Mon-El. When season three returns with all-new supercharged adventures this fall on The CW, Kara and team will come up against a new threat in the form of DC Worldkiller, Reign.

Supergirl returns for its third season Monday, October 9, at 8/7c on The CW. Based on the DC characters created by Jerry Siegel and Joe Shuster, the series is executive produced by Greg Berlanti, Andrew Kreisberg, Sarah Schechter, Robert Rovner and Jessica Queller. Supergirl is produced by Berlanti Productions in association with Warner Bros. Television. Last month, Jessica Queller and Robert Rovner were named co-showrunners of the series, serving alongside co-creator Andrew Kreisberg. They take over for departing executive producer Ali Adler, who has signed an overall deal with CBS Television Studios, to work on the new Dynasty series, although she will remain with Supergirl as an executive consultant. Take a look at the new Supergirl Season 3 trailer below.