Tim Allen wasn't so jolly on set, according to a former costar.

Casey Wilson accused the Toy Story alum of being difficult to work with on their 2022 Disney+ series The Santa Clauses, the latest installment of The Santa Clause franchise, which kicked off in 1994 with Allen playing divorced-dad-turned-Father Christmas Scott Calvin.

"Tim Allen was such a b---h," Wilson said on a recent episode of her Bitch Sesh podcast. "Worst, truly single worst experience I've ever had with a co star ever."

The Happy Endings actress, 43, recalled filming one scene in which her character—the older version of lactose intolerant Sara—sees Santa (Allen) enter her home and thinks he's a burglar. 

"I'm supposed to throw things at him," Wilson explained. "He's coming down the chimney, obviously as Santa. And I am woken up thinking there's an intruder—basically like a home invasion scene." 

However, she said Allen wasn't thrilled by her performance so he went over a producer standing a few feet away from her.

"I basically hear him—he goes, 'You gotta tell her to stop stepping on my lines,'" Wilson continued. "The producer turns to me with horror on his face and has to walk one foot to me and he goes, 'Tim would ask that you stopped stepping on his lines.'"

She added, "When he was done, he was so f--king rude. Never made eye contact, never said anything. It was it was so uncomfortable."

E! News has reached out to Disney and Allen's rep for comment but hasn't heard back. 

Allen stepped back into the big red suit last year, more than 15 years after the third movie was released.

"As I walked on set for the first time in the full regalia, everybody got very quiet, both adults and kids," the Home Improvement star told Entertainment Weekly ahead of the show's premiere. "When I show up dressed in the full suit and everything else, there's big smiles on people's faces. Little kids are quiet. I had totally forgotten that. It does feel like Santa's in the room."

The 70-year-old also got to share the experience with his real-life daughter Elizabeth Allen-Dick, 14, who made her acting debut as Santa's daughter Sandra.

"It's difficult to believe, but it had very little to do with me," he confessed of her casting, though he acknowledged that she's been around Hollywood all her life. "We got to play all the time as a comedian. I'm that way around the house. She's able to take a line, make it her own, add value to it and be honest about it. And it was an amazing experience." 

Read on for more frosty secrets about The Santa Clause franchise:

1. The original name of the movie was Such a Clatter.

2. Other actors considered for the role of Scott Calvin/Santa Claus were major stars like Tom Hanks and Mel Gibson, according to an interview first-time film director John Pasquin gave on the Grunt Work podcast. And it was Bill Murray who was reportedly the top candidate. But after starring in the Christmas classic comedy Scrooged, Murray "had no interest in pursuing another holiday-themed project," shared Pasquin.

3. But producers weren't totally sold on Tim Allen despite Home Improvement's wild popularity. In a 2011 episode of Biography screenwriters Steve Rudnick and Leo Benvenuti shared that producers claimed Allen "can't open a movie, he's a TV star."

4. Allen's Home Improvement wife Patricia Richardson and Everybody Loves Raymond star Patricia Heaton were considered for the role of Laura, but Wendy Crewson ultimately landed the role of Scott's ex-wife.

4. Judge Reinhold nabbed the part of Laura's spouse (and Scott's nemesis) Neal Miller, though Jeff Daniels, Stanley Tucci, and Bradley Whitford were considered. He would go on to appear in all three films.

6. The hardest role to cast was Charlie, Scott's son, as they were looking for a child actor between the ages of 6 and 9, "who had sensitivity" casting director Renee Rousselot shared and was "able to really access those emotions, but have a real innocence about him." The production team launched open auditions in 13 different cities before finding Eric Lloyd.

7. During filming of the original movie, Lloyd had to wear dentures after knocking out his front teeth when he went to a baseball game with his family. Oh, and that poster image of Scott and Charlie? It wasn't actually Lloyd's body, with the actor revealing on Reddit in 2014, "It's some other kid standing behind a cutout of Tim Allen. And they just put my face on it. So they didn't have to pay me for another day."

8. The original script was much darker, with Scott actually shooting Santa Claus as he believed he was a robber. However, Allen revealed on The Tonight Show in 2018 that DreamWorks CEO Jeffrey Katzenberg  "was adamant, 'We can't start a movie like that.'"

9. Peter Boyle plays Scott's boss in the first film but would go on to star in the next two movies as a different character: Father Time. 

10. Allen's Home Improvement co-star Jimmy Labriola (Benny) makes a brief appearance in the film as a truck driver Scott and Charlie ask a question from while they are in the sleigh.

11. Allen underwent four to five hours of makeup and prosthetic applications to transform in Santa (and that doesn't count the two hours it took to take it all off) and had to wear multiple fat suits during filming, which took place in the middle of summer. "You can't describe how maddening the process is," Allen said of getting into character as Kris Kringle, calling it "terrible." Because of the latex, Allen experienced heat rashes, scars, scratches and infections. 

12. There was a time limit on how long Allen could be in the suit while filming, maxing out at six hours because of the poor ventilation. "They got better and better at air-conditioning me, just keeping me calm," Allen told ABC News of the later films. 

13. Casting real children as the North Pole's elves proved a bit challenging for Allen, who was known to improvise on set. "You didn't want the kids around when Tim got going," actress Crewson said on Biography. "He would go on these hilarious rants, streaked through with obscenity." This lead to production pulling their star away for the occasional "time out" when he seemed close to cursing. 

14. Allen had to go back and re-record many of his lines because of the sounds the bells on the Santa suit made. He later explained he had to use Automatic Dialog Replacement for most of that film because people [said], 'What's all that ringing?' And it was me walking."

15. While filming, Allen was also writing his first book, so "any break I had, I had a guy in my trailer, like, 'So can we get started with work?'" he shared on ABC News. "And I had just kind of left a job...that was a really stupid thing on my part."

16. But all the hard work paid off: Allen had the No. 1 movie at the box office, the No. 1 show on TV with Home Improvement and was at the top of The New York Times Best-Sellers list with Don't Stand Too Close to a Naked Man. 

17. The original script focused more on Charlie outside of his relationship with his dad (meaning scenes without Allen in them), but the running time was deemed too long for children so the scenes were cut. The scenes included Charlie struggling with his dad's transition into Santa Claus and dealing with bullying at school. Overall, more than 30 minutes of footage was cut. 

18. Old DVD releases of the film include a line that was later removed, with Scott making a joke about calling "1-800-SPANK-ME," which the filmmakers did not realize was a real phone number for a sex line. Disney received complaints about children calling the number and decided to cut the line from the movie moving forward.

19. In its opening weekend in early November 1994, The Santa Clause debuted at No. 2 behind Interview With a Vampire, making $19 million, almost the same amount as the film's total budget. But then something strange happened: It kept performing, ultimately landing at No. 1 at the box office almost one month after its premiere. By Christmas, it had made well over $100 million in the U.S. alone. 

20. Given the surprise success of the first film, Disney was keen on doing a sequel, but Allen wanted to wait and make sure it would be a worthy follow-up. At one point, 16 different contributors had been involved in The Santa Clause 2, which finally hit theaters in 2002, with Allen almost walking away at a certain point. "We gave up. We got to the point where we all got frustrated," he told One Guy's Opinion. "They greenlit the script, and I said I don't want to do this. But we pushed through."

21. Despite continuing to work together on Home Improvement, Pasquin did not return to direct the follow-up films and Allen credited new director Michael Lembeck for helping make the sequel possible. "The studio and I were really disagreeing on which direction to take it if we were going to take it at all," the star explained to One Guy's Opinion. "We really didn't think they were going to do this. We were so far apart. And then Michael came in...and made the thing. He came to the set every day with an attitude that was great."

22. David Krumholtz (a.k.a. Bernard the Elf) revealed two surprising fans of the film: Khloe and Kim Kardashian. "They came up to me and said, 'We've seen The Santa Clause a hundred times!'" In fact, it's a tradition for the Kardashian family to watch the movie each Christmas Eve.

23. Krumholtz could not reprise the fan-favorite role of Bernard in the third and final film due to scheduling conflicts with his hit CBS procedural Numbers. 

24. Kelly Preston, Jennifer Connelly and Brooke Shields were all reportedly considered for the role of Carol (aka the future Mrs. Claus) for The Santa Clause 2, with Lost star Elizabeth Mitchell ultimately being cast. 

25. For the third film, The Santa Clause 3: The Escape Clause, Martin Short joined the cast as Jack Frost, Santa's rival. Allen and Short had previously worked together on 1997's Jungle 2 Jungle.