HBO’s Luck headache has returned.

The network was hit with a lawsuit over its beleaguered and ironically titled short-lived horse-racing drama. A former employee of the American Humane Association who worked on the show is accusing the network and producers of mistreating horses and says the animal rights organization aided in a cover-up of the abuse.

Barbara Casey was the director of production on the AHA’s film and TV unit and a longtime veteran of the organization. She served as a liaison between the animal rights institution and production companies. In a lawsuit filed in Los Angeles Superior Court this week, Casey says horses were drugged, and that sick and underweight horses were forced to work on the show. Casey also claims animals were misidentified to make it more difficult for safety representatives to track their medical histories. “In order to save time and money [the defendants engaged in] direct criminal animal abuse and cruelty … [and] pressured AHA to allow them to violate AHA’s safety standards,” reads the suit. “[And to] allow the use of unsuitable horses in an attempt to ensure that sufficient numbers of horses would be available to meet its production demands.”

Casey claims she wanted to contact law enforcement about the mistreatment, but that AHA fired her for threatening to speak out in January 2012. “AHA bowed to political and financial pressure and refused to report the Production Defendants’ conduct to the authorities,” reads the suit. “AHA terminated Plaintiff’s employment in order to prevent her from reporting the …violation of animal abuse.”

HBO cancelled Luck in March after at least three horses died on the show and PETA launched a protest.

HBO said in a statement: “We took every precaution to ensure that our horses were treated humanely and with the utmost care, exceeding every safeguard of all protocols and guidelines required of the production. Barbara Casey was not an employee of HBO, and any questions regarding her employment should be directed to the AHA..”

The AHA famously coined the stamp of approval “no animals were harmed” in the making of Hollywood productions and did not reply to a request for comment.

What do you think? At this point, is suing over HBO’s Luck simply beating a dead horse?