There's lots of new stuff coming to Supergirl season 2, including former Wonder Woman Lynda Carter as The President!

Lynda Carter, who played Wonder Woman on TV from 1975 to 1979, will soon make her return to the DC universe as the President of the United States on Supergirl season 2 episode 3, "Welcome to Earth."
Here's the official synopsis from the CW:
An attack is made on the President (guest star Lynda Carter) as hot-button, alien vs. human rights issues heat up in National City. Supergirl (Melissa Benoist) and the DEO are assigned to protect the President and bring in the responsible party. Alex (Chyler Leigh) teams up with Detective Maggie Sawyer (Floriana Lima) to investigate the case while Kara searches for a recently escaped Mon-El (Chris Wood), who she fears may be the alien behind the assault.
Check out the trailer:
Rachel Talalay will direct the episode, which airs on October 24th.
This is something that had been considered for season one, but it didn't work out. "We had the perfect role for Lynda Carter," Supergirl executive producer Greg Berlanti said back in March, long before Supergirl Season 2 had been confirmed. "We couldn’t work out her schedule. Next year."
Nice to see that they keep their promises.

Check out the official images of Lynda Carter as the President in the gallery up top!
Berlanti and Kreisberg's DC shows have featured several appearances from past DC TV stars, such as Dean Cain (Lois & Clark: The New Adventures of Superman), Helen Slater (1984's Supergirl film), Laura Vandervoort (Supergirl on Smallville), Mark Hamill (the 1990s Trickster), and John Wesley Shipp (1990s Flash). Ms. Carter will certainly be another welcomed addition to this universe.
Watch Supergirl Season 1 on Amazon
Supergirl Season 2 Episodes
Supergirl Season 2 Episode 1: The Adventures of Supergirl
When a new threat emerges in National City, Kara/Supergirl (Melissa Benoist) teams up with her cousin, Clark Kent/Superman (guest star Tyler Hoechlin), to stop it. Kara is thrilled to have family in town but it leaves Alex (Chyler Leigh) feeling a bit left out. Meanwhile, Hank (David Harewood) and Supergirl are stunned by the pod that came crashing to Earth.
air date: 10/10/16
Supergirl Season 2 Episode 2: The Last Children of Krypton
CADMUS attacks National City with a kryptonite powered villain who ends up seriously hurting Supergirl (Melissa Benoist). Superman (guest star Tyler Hoechlin) blames Hank (David Harewood) because the kryptonite was stolen from the DEO. Meanwhile, Kara’s first day at her new job doesn’t go as planned after she meets her new boss, Snapper Carr (guest star Ian Gomez).
We also have a complete guide to Superman easter eggs in the episode right here!
air date: 10/17/16
Supergirl Season 2 Episode 3: Welcome to Earth
An attack is made on the President (guest star Lynda Carter) as hot-button, alien vs. human rights issues heat up in National City. Supergirl (Melissa Benoist) and the DEO are assigned to protect the President and bring in the responsible party. Alex (Chyler Leigh) teams up with Detective Maggie Sawyer (Floriana Lima) to investigate the case while Kara searches for a recently escaped Mon-El (Chris Wood), who she fears may be the alien behind the assault.
air date: 10/24/16
Supergirl Season 2 Episode 4: Survivors
With all of the hype about the Justice Society coming to Legends of Tomorrow, it's worth noting that Supergirl season 2 episode 4 will introduce a version of a JSA villain, in the form of Roulette (played by Dichen Lachman).
Here's the official synopsis:
When Kara (Melissa Benoist) and Alex (Chyler Leigh) investigate the murder of an unregistered alien, the trail leads to an alien fight club run by Roulette (guest star Dichen Lachman), the ringmaster who commands aliens to fight in mortal combat for the entertainment of rich humans. While trying to stop the fighting, Supergirl and Martian Manhunter find themselves up against a surprising opponent. Meanwhile, Hank (David Harewood) is thrilled to have found another Martian and tries to get to know M’Gann (guest star Sharon Leal) better. Supergirl takes Mon-El (Chris Wood) under her wing and begins to train him.
There's a hint of a Legends of Tomorrow connection here, too. Roulette first appeared in JSA Secret Files #2 in 2001, and was introduced as a Justice Society villain. Since the JSA are such a major factor in Legends of Tomorrow Season 2, perhaps this is an indicator that there will be some additional opportunity for crossovers. But her MO is mostly the same here as it was in the comics (although she ran a superhero fight club not an alien one in the comics).
air date: 10/31/16