Amanda Seyfried said she went to some “scary, dark places” for her latest role in Long Bright River, playing a beat cop on the mean streets of Philadelphia.

In the eight-part drama, produced by Sony Pictures Television, which dropped on Peacock+ on March 13 and will have its international premiere at TV festival Series Mania in Lille this week, Seyfried plays Mickey, a Philly-raised overachiever who it once seemed was bound to escape her blue-collar roots. Instead, she finds herself a single mom patrolling her own Kensington neighborhood, trying to connect with the addicts and sex workers she encounters every day. One of them is her own sister, Kasey (played by Ashleigh Cummings), who has ended up, literally, on the wrong side of the tracks. When sex workers start turning up dead, and Kasey vanishes, Mickey suspects a serial killer is on the loose and that her sister could be his next victim.