With Lifetime's 'Unauthorized Saved by the Bell Story' airing on Sept. 1, fans are regarding the tell-all TV movie kiiind of like a car accident: It may be a wreck, but we just can't look away. In honor of the upcoming film, we're looking back at the cast of 'Saved by the Bell' -- then and now. What have the students of Bayside been up for the past 20 (!) years? And what do they think of the upcoming Lifetime movie? Find out below.

Mark-Paul Gosselaar (Zack Morris)

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Then: Bleach blonde Mark-Paul Gosselaar played the scheming-but-lovable Zack Morris in 'Saved by the Bell' and its multiple incarnations, including 'Good Morning Miss Bliss,' 'Saved by the Bell,' 'SBTB: The College Years,' the TV movie 'SBTB: Wedding in Las Vegas,' and one episode of 'SBTB: The New Class.' Two years after his last portrayal of Zack, Gosselaar starred opposite fellow '90s teen star Candace Cameron in the Lifetime movie 'She Cried No,' in which he played a very un-Zack-like role as a rapist. Yikes.

Now: Gosselaar went on to have continued success on the small screen, starring as Detective John Clark on 'NYPD Blue' for five years before playing a lawyer on both 'Raising the Bar' and 'Franklin & Bash.' And to all the ladies still harboring a not-so-secret crush on Zack Morris: Gosselaar is happily married to his second wife, with whom he has one son. He also has another son and daughter from his first marriage.

Thoughts on the 'SBTB' Lifetime movie: "Everything I've heard about [Dustin Diamond's] book is, it is negative," he told the Huffington Post. "I don't remember those things. My experience on the show was very positive."

Tiffani Amber Thiessen (Kelly Kapowski)

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Then: What '90s girl didn't want to be the brunette, feather-haired Kelly Kapowski (or Tiffani Amber Thiessen for that matter)? Like Mark-Paul Gosselaar, Thiessen played the role of Kelly in many variations of the beloved sitcom, including 'Saved by the Bell,' 'SBTB: The College Years' and 'SBTB: Wedding in Las Vegas.' After the show ended, she immediately was cast in another career-defining role as bad girl Val on 'Beverly Hills 90210' -- a part she played for four years.

Now: Thiessen finished up the '90s with starring roles in dramatic television movies, continuing to act throughout the first decade of the 2000s. Happily married since 2005 and a mom of one, Thiessen currently stars on 'White Collar' as Elizabeth Burke, a role she's played since 2009.

Thoughts on the 'SBTB' Lifetime movie: Thiessen has not commented on the movie.

Mario Lopez (A.C. Slater)

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Then: Like most of his co-stars, Mario Lopez not only played muscular wrestler A.C. Slater for five seasons on 'Saved by the Bell,' he went onto continue that love of unitards in 'SBTB: The College Years,' 'Wedding in Las Vegas' and the final episode of 'SBTB: The New Class.' Fun fact: The dimpled star also guest-starred in an episode of 'Bill Nye the Science Guy.'

Now: In 2006, Lopez placed second on 'Dancing With the Stars,' with then-girlfriend Karina Smirnoff as his partner. The actor has hosted the entertainment talk show 'Extra!' since 2008, also starring in the Broadway production of 'A Chorus Line' that same year. In 2012, he extended those hosting duties to 'The X Factor' for two seasons. Lopez has been married to his second wife (his first marriage with Ali Landry was annulled) since 2012, and the couple have two kids together, whom they proudly (and frequently!) show off on Instagram.

Thoughts on the 'SBTB' Lifetime movie: While interviewing his former co-star Elizabeth Berkley and asking her thoughts about the Lifetime flick, Lopez was honest about his own feelings, saying: "The key word is unauthorized."

Elizabeth Berkley (Jessie Spano)

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Then: Elizabeth Berkley played strong-willed, politically active (and for one memorable episode, caffeine pill-addicted) Jessie Spano on 'SBTB.' And while she came back for Zack and Kelly's wedding in 'Wedding in Las Vegas,' unlike her other co-stars, Berkley's Jessie Spano did not continue on to the fictional Cal U in 'The College Years.' The actress did, however, go on to earn an infamous starring role in 1996's NC-17 rated 'Showgirls.'

Now: Berkley went on to have a critically acclaimed career in theater, starring in shows on London's West End, Broadway and Off-Broadway, alongside such big names as Eddie Izzard, Richard Dreyfuss, and Ethan Hawke, respectively. She's also shared the screen with Al Pacino in 'Any Given Sunday,' scored a part in Woody Allen's 'The Curse of the Jade Scorpion,' and even played a falsely accused teacher in the Lifetime movie 'Student Seduction.' (Our total guilty pleasure!) The blonde bombshell, who is also an animal rights activist, has been happily married to her hunk of a husband Greg Lauren (Ralph's nephew) since 2003, and the two have one child together.

Thoughts on the 'SBTB' Lifetime movie: "We know the lives we lead, and I think they're taking it off the unauthorized book by Dustin Diamond. It's a little silly to give credence to that, when we know the innocence and joy that we shared," she told her former co-star Mario Lopez on 'Extra.' "It's not even real."

Dustin Diamond (Samuel 'Screech' Powers)

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Then: Curly-haired Dustin Diamond starred as goofy Screech for almost 13 years, playing the lovable nerdy character in every version of 'Saved by the Bell' from 'Good Morning, Miss Bliss' to 'SBTB: The New Class,' in which Screech became Mr. Belding's assistant.

Now: Post-'SBTB,' Diamond's career veered onto a very different path. He created his own sex tape called (we kid you not) 'Screeched: Saved by the Smell' -- though he claims to have used, quote, a "stunt wang." He also participated in several reality television shows, including 'Celebrity Fit Club' and 'Celebrity Big Brother.' Of course, Diamond also wrote 'Behind the Bell,' the tell-all book that the upcoming Lifetime movie is based on (he'll be serving as executive producer) -- though he has admitted to feeling regret over releasing the book. Hmmm.

Thoughts on the 'SBTB' Lifetime movie: Considering the fact Diamond is serving as executive producer on the movie, which, as we noted, is based on his 2009 tell-all book 'Behind the Bell,' (he now claims it was written by a ghost writer), it's not really that surprising that the actor is excited for the portrayal. He told the Daily Beast:

"I think when this movie comes out, it’s going to surprise people because it’s not salacious, it’s not dirty, it’s not negative. It’s embracing all the positive things that happened and clarifying certain things. I think it’s going to be pretty enjoyable. I think everyone’s going to like it, including the other cast members."

Lark Voorhies (Lisa Turtle)

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Then: Lark Voorhies played fashionista Lisa Turtle on 'SBTB,' later appearing in just one episode of 'SBTB: The College Years,' though she also returned for 'Wedding in Las Vegas' and the final episode of 'SBTB: The New Class.'

Now: Though Voorhies has continued to act since 'SBTB,' her career has since stalled (her last film role was opposite her former co-star Dustin Diamond in the 2012 direct-to-video 'The Little Creeps'). Today, the actress sadly appears to be suffering from mental health issues. In 2012, her mother told PEOPLE that Voorhies was bipolar, and the actress herself admitted to struggling with her mental health -- though she denied that she was suffering from bipolar disorder, schizophrenia or any other condition. Voorhies continued to deny these claims in an erratic interview with 'Entertainment Tonight.'

Thoughts on the 'SBTB' Lifetime movie: Voorhies has not commented on the movie.

Dennis Haskins, Mr. Belding

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Then: Dennis Haskins portrayed principal Mr. Belding for every incarnation of 'SBTB' there was, from 'Good Morning Miss Bliss' straight through to 'SBTB: The New Class.' Of course, it was on 'Saved by the Bell' itself that he and his trademark catchphrase, "Hey, hey, hey, what's going on here?" that he truly won our hearts.

Now: Haskins has since added a wealth of credits to his name, including roles in 'Max Keeble's Big Move,' 'Victorious' and bit parts in 'Mad Men' and 'How I Met Your Mother,' and, most recently, as a snake oil salesman in Seth MacFarlane's 'A Million Ways to Die in the West.' But most importantly, Haskins (who once released an album called 'Karaoke With Your Favorite Principal Dennis') is active on Twitter -- and his handle is @mrbelding. It doesn't get any better than that.

Thoughts on the 'SBTB' Lifetime movie: "I was there. I know what happened and didn't happen," he told TMZ. "Who do you believe: The people that were there … or [Diamond] who says he just got on the phone with a guy and the next thing [he] knew, [the ghostwriter] wrote all these things and [he] didn't know he'd written them, and now he's the executive producer on the movie?"