Black-is is one of the top sitcoms in America, and two of its castmembers Tracee Ellis Ross and Jennifer Lewis hate each other. According to a new report on Radar Online, the two ladies went at it during the taping of a recent episode.

The report claims that Tracee started off being deferential to the older actress. But when Tracee reached her breaking point, she lashed out at Jennifer - and cursed her out.

Here's what is being reported:

“Tracee can’t stand Jennifer and vice versa, they’re like oil and water, they don’t mix well,” says the source. “They’re just like their characters — Jennifer wants to be the boss and Tracee isn’t having it.”

According to on-set insiders, the entire production shut down for about 30 minutes a few weeks ago because of the drama between the two actresses.

Source says there were some heated words exchanged between the two women after Lewis called out Ross for talking while she was trying to read her lines.

The mag claims that Tracee used profanity during her tirade.

The report is a bit odd because Tracee has the reputation of being a very easy going and likable person on set.

On the other hand, Jennifer's reputation is a little dicey. She has the tendency to be a little "over the top" when working on productions.