Reese Witherspoon on The Tonight Show stil

NBC via The Tonight Show Starring Jimmy Fallon/YouTube

Word came in January that none other than Meryl Streep had joined "Big Little Lies" Season 2, but what was missing from reports at the time was the hilarious way the three-time Oscar winner accepted her role.

Luckily, that has changed. Reese Witherspoon was recently a guest on "The Tonight Show Starring Jimmy Fallon," and the late-night host asked her how Streep got involved. Witherspoon then kindly told him the whole tale.

It started out pretty much how you'd expect: Witherspoon and her fellow executive producer and co-star Nicole Kidman sent Streep the script. Then, they followed up via email. It was after that that Streep gave them a call -- and accepted in funny fashion.

"She called us the day of the Golden Globes, and was like, 'Well, I know your show is really struggling ... so I've decided to join and make it even better," Witherspoon told Fallon, laughing as she claimed that Streep's comment was true.

Of course, the show wasn't exactly hard up for either talent or accolades. At the very same Golden Globes that Witherspoon referenced, the drama won the award for Best Miniseries or Television Film, while Kidman, Alexander Skarsgard, and Laura Dern all took home individual awards. That's what makes Streep's comments so entertaining, combined with the fact that she's Meryl Streep and almost definitely will make it even better.

Witherspoon and Kidman loved Streep's response, too. Witherspoon said she and her co-star were screaming silently and hugging themselves when she gave them the news. Aww!

Watch Witherspoon tell the story below, starting at 1:23.

"Big Little Lies" Season 2 is expected to premiere in 2019. "The Tonight Show Starring Jimmy Fallon" airs weeknights at 11:35 p.m. ET/PT on NBC.