A documentary depicting the daily workings of the Richard Mandella stable will premiere at Del Mar next Sunday. Shortly after the last race is run on that day's card, the first hour of "On the Muscle: A Year Inside a Thoroughbred Racing Barn" will be shown on the large screen in Del Mar's paddock.The limited series documentary is the loving creation of a pair of award-winning filmmakers - and Robin Rosenthal - who spent a full year with the barn of trainer Richard Mandella, chronicling the ups, downs, ins and outs in the life of the Hall of Fame conditioner and his stable of Thoroughbreds. "I have been making films for 35 years," said Bill Yahraus, who made the film along with Robin Rosenthal, "but this is the most ambitious project I've ever worked on. The commitment of time and energy was enormous, both for us and Richard. I can't say enough about him. He was a man of his word; once he agreed to the project, he never backed off. I'm sure there were days when he thought 'Oh, no, here they come again,' but he never backed off his promise."Daily filming began at Santa Anita in January of 2002, with the filmmakers then following the Mandella horses to Hollywood Park, Kentucky, Del Mar, Oak Tree, the Breeders' Cup at Arlington Park in Chicago, back to Hollywood Park, and then to Santa Anita again to finish up the year. "And he (Mandella) never once said 'Don't film this,'" Yahraus noted. "We asked him for total access and he allowed us that every day. He was completely open. We'd just show up and start filming; no phone calls, no warnings. He just stuck to his business and he let us do ours." The documentary, which focuses on Mandella and several horses in his large stable, includes an inside look at their care, training and racing, as well as surgeries and rehabilitations. "It is an unprecedented attempt at an extended and extensive look at the world of Thoroughbred racing, up close and very personal," notes a Del Mar press release. The husband-wife team of Yahraus-Rosenthal also created the 1999 PBS documentary "Travels With Tarzan," which told the story of a family-owned tent circus' season on the road. "Both of the settings - the circus and the racetrack - are worlds unto themselves," Rosenthal said. "They are both exotic; they both have their own language. There are strong parallels there. And the challenge for us was to weed through so many choices and condense it into something both entertaining and informing. We wanted to be able to tell a story that people on the outside could understand, yet we didn't want to make it so simple that we were talking down to the insiders. We think we've done that with 'On the Muscle,' and one of the reasons is that we were working with Richard - an excellent horseman and an intelligent individual who has many levels to him. I think those who watch it will see that -- see what a special person he is." The son of a blacksmith, 52-year-old Mandella has spent most of his life around horses and went on his own as a trainer in 1976. In 2001, Mandella was inducted into the National Museum of Racing's Hall of Fame."When they approached me in the fall prior to starting this thing," Mandella said, "they told me they wanted to do a 'real life' documentary on racing. They said they wanted to do a sort of fly-on-the-wall thing; not one where they'd be doing a lot of interviews. Just sort of letting it happen. When I thought about it, I realized it might be a good thing for racing. Unfortunately, many of the movies I've seen about racing have to do with guys setting up scams or drugging horses. But, you know, there's a lot of hard, honest work in this game. There's a lot of care given to horses. There's a lot of love of the game that goes into the business. So I thought that if they did something truthful - really showing what goes on on the backside on a regular basis -- I thought it would be a fair shot for racing; I thought it might be good for everyone involved. And if I could be part of that, I wanted to be involved. I have nothing to hide at my barn, so I told them 'Yes'."Mandella I unsure of how the final product turned out, but said having the cameras around the barn all the time was an overall good thing."Well, I haven't seen the piece yet, so I can't be too sure how it all came out," he said. "But they were good people to work with. They stayed out of my way as much as you can in that situation. And they made me realize I shouldn't cuss so much around the barn. And that's a good thing."Using a small digital camera, Yahraus and Rosenthal shot 260 hours of video, with a plan to produce a two-hour movie. "But once we got into the process, we learned we had an embarrassment of riches," Rosenthal said. "We tried, but we simply couldn't cut it to two hours. We finally settled on three and we're still working our way toward a final product. What we'll be showing at Del Mar is the first of three one-hour episodes. Normally, a one-hour documentary is about 52 minutes, but what you'll see that Sunday will be about 1:15. We're still scoring the music and adding final touches."The first hour consists of the stable's winter meet at Santa Anita and introduces the main characters -- both human and equine. The second hour is Hollywood Park, Kentucky and opening day at Del Mar. And the third hour goes through Del Mar, Oak Tree, the Breeders' Cup and finishing out the year." Yahraus, Rosenthal, and Mandella will be available for an audience question-and-answer session both before and after the screening on Sunday. The filmmakers will be taking the first episode to Cannes, France to the in October in search of a buyer for the series."I think we've put together a wonderful piece," said Yahraus. "The way we were able to work - very light and very mobile and with full access - allowed us to get a close-up of racing that normally isn't done. It is a very intimate film. It has the real texture of racing and the people and the horses. We're quite proud of it and I hope that people involved in the game will feel the same way."