The drama, from White Collar creator Jeff Eastin, focuses on a group of federal agents who live together in a house in California.
Thompson has now signed up to play a DEA agent called Lauren Kincaid, TV Line reports.
Lauren is said to be dealing with the aftermath of her partner getting wounded.
Thompson has previously appeared in shows such as Trauma, Brotherhood and NCIS.
She will be joined in Graceland by stars including Daniel Sunjata, Aaron Tveit, Brandon Jay McLaren, Vanessa Ferlito and Manny Montana.