An attack is made on the President as hot-button, alien vs. human rights issues heat up in National City. Supergirl and the D.E.O. are assigned to protect the President and bring in the responsible party. Alex teams up with Detective Maggie Sawyer to investigate the case while Kara searches for a recently escaped Mon-El, who she fears may be the alien behind the assault.
- Melissa Benoist as Kara Danvers/Supergirl
- Mehcad Brooks as James Olsen
- Chyler Leigh as Alex Danvers
- Jeremy Jordan as Winn Schott
- Floriana Lima as Maggie Sawyer
- Chris Wood as Mon-El
- David Harewood as J'onn J'onzz/Martian Manhunter
Special Guest Star
- Sharon Leal as M'gann M'orzz
- Katie McGrath as Lena Luthor
- Nadine Crocker as Scorcher
- Ian Gomez as Snapper Carr
- Jaeson Lee as DEA Agent #1
- Jayson Li as Astronomer
- Kaylee Sapioha as Darla
- Iris Truong as Young Girl
- Jason Vaisvila as Boris
- Robert Zon Humpage as Fish Hood
- Leen Kaplov as Four Eyes
- Stephanie Lavigne as Half Extreme Alien
- Gary Starkoll as Gary Forehead
- This is the first episode to not feature Cat Grant, following Calista Flockhart being downgraded to special guest star due the series relocation to Vancouver.
- A veiled reference is made to Diana Prince/Wonder Woman's Invisible Plane when President Olivia Marsdin tells Supergirl "you ought to see my other jet". Lynda Carter, who portrays the President, also portrayed Wonder Woman in the live-action series of the same name (1975-1979).
- Another reference is made to Diana Prince's spin transformation from the Wonder Woman TV series: when Supergirl notices she's on fire, she does a similar spin to put out the flames.