Sonar Entertainment, Inc., formerly known as Cabin Fever Entertainment, Hallmark Entertainment and RHI Entertainment, is an American producer of television movies and miniseries, founded in 1979 by Robert Halmi Jr. and Robert Halmi Sr. (1924-2014) as Robert Halmi Incorporated.

In 1988, the Halmis merged their company with Hal Roach Studios to form Qintex Entertainment, named after the Australian company that bought a share in the new venture. After Qintex's downfall, the company's assets were acquired by RHI Entertainment, with New Line Cinema and Chemical Banking Corporation acting as shareholders.Hallmark Cards purchased RHI in 1994 and renamed it to Hallmark Entertainment. In 2006, the Halmis, along with affiliates of Kelso & Company, reacquired the company and revived the RHI name.

In 2007, RHI began offering premieres of its films to digital cable customers of Time Warner Cable, Bright House Networks, Cablevision, Cox Cable and Comcast, via the video on demand service. Also that year, RHI licensed a number of its new movies, miniseries and back catalog titles to global subscribers of Apple's iTunes service.