"Supergirl" season 5 episode 13 is going to be a special segment because it happens to be the 100 th episode of The CW series. As the show is headed towards a big milestone, things are just about to get more adventurous on Earth-Prime. If you are curious about this chapter of the series, read on to find out what happens next.

[Spoiler alert! This article contains spoilers for "Supergirl" season 5 episode 13. Do not read further if you don't want to know more about it.]

The thirteenth episode of the fifth season of "Supergirl" carries a title "It's a Super Life" and it brings to the town a special character. Mister Mxyzptlk, also known as Mxy, is here to woo Kara Denver once again. The reality-bending trickster from the 5th dimension is being played by "Reno 911: Miami" star Thomas Lennon.

He is back in town with an interesting proposition for the Supergirl. He offers to help her to go back in time and change things with Lex. Mxy presents Kara with an opportunity to travel back in time and tell Lena the secret about her true identity before Lex did. The offer gets Kara wondering what would have happened if things happened differently. As she relives the key moments, she finds herself tempted to change history. But will she do it? The official synopsis suggests that Kara is conflicted, but it remains to be seen what her decision will be. In addition, the show features the return of some familiar faces in the 100th episode.

Meanwhile, speaking to TV Guide, Nicole Maines confirmed the return of several beloved characters for the special episode.

"The most exciting part — because we know we have a lot of people coming back — is just getting to work with cast members that I've not gotten a chance to interact with on set before," Maines said.

Melissa Benoist as Supergirl in new CBS series CBS

Meanwhile, fans are looking forward to meeting Kara's ex Mon-El since he left the series after season 3. Even though the identities of the characters returning to the show remain unspecified, many fans and media outlets are speculating the return of Chris Wood's character. It was earlier confirmed that Wood was in Vancouver during the hundredth episode of the series and he even attended the party.

"Supergirl" season 5 episode 13 airs Sunday, February 23 on The CW.