The rats are probably the worst part.

One of the little charms of life inside Los Angeles County Men’s Central Jail is that even in solitary confinement, an inmate is never truly alone; it’s a tribute to the facility’s resourceful rodent population. Up in cellblock 1700, the same third-floor row of solitary cement stalls used to hold O.J. Simpson and the Menendez brothers, inmate No. 5478610 — Robert John Downey Jr. — tackles the rat problem with a variation on an old Boy Scout trick: After a meal, the 32-year-old Academy Award-nominated actor will sometimes hang his leftover mystery meat high overhead so that the rodents can’t snap it up.

Conventional wisdom says that celebrities get all the lucky breaks, even when their luck runs out. But despite the objections being raised by what some are calling Downey’s special privileges while incarcerated — from a plastic-surgery outing to a studio jaunt that included a pit stop at Downey’s Hollywood home — he’s hardly getting the star treatment. Compared with the cushier La Verne city jail just outside L.A., where Christian Slater did his time for assault until last week (and where inmates can use laptop computers and microwave ovens), the rough-and-tumble, overcrowded county jail sounds more like Midnight Express.

”It’s hellish,” says Downey’s lawyer, Ira Reiner, a former Los Angeles district attorney, who is also one of the few people in contact with the gifted star of Chaplin, Natural Born Killers, and Home for the Holidays. ”There’s nothing too happy about it. County jail is a dirty, ugly, noisy, dangerous place with bad food. There’s nothing about it I can recommend.”

It was also, unfortunately, the only place left for the out-of-control actor to go. Downey has been a California jail system headliner since June 23, 1996, when he was pulled over for speeding on the Pacific Coast Highway, and Malibu police uncovered heroin and crack cocaine along with an unloaded .357 Magnum in his black Ford Explorer. Spending the remaining months of 1996 in supervised rehabilitation (see timeline on page 38), he stayed clean, submitting to periodic drug tests until he suffered a relapse during a break in the filming of Warner Bros.’ U.S. Marshals last September.

At Downey’s probation violation hearing Dec. 8, Malibu municipal court judge Lawrence Mira, palpably angry and frustrated with the wayward star, doled out a tough sentence: 180 days to be served in the county jail. ”You need to find out why…you are willing to endure so much pain and turmoil in your life to continue doing drugs,” Mira upbraided Downey. ”I’m going to send you to jail…. I don’t care who you are.”

Some mornings, Robert Downey Jr. gets his wake-up call as early as 5 a.m. A light is switched on and his first meal of the day is delivered to his 9- by 12-foot cell. He’s entitled to three meals, usually at 6:30 a.m., 11 a.m., and 4 p.m. — with two guaranteed warm ones, like chipped beef on toast or lasagna.