After lengthy deliberations, WGN America has opted not to order a third season of its period drama series Manhattan. The show, from Lionsgate TV, Skydance TV and Tribune Studios, was well received by critics but it was a modest ratings performer and, with its sprawling Los Alamos setting, it was expensive. Still, the drama about the birth of the Manhattan Project had a lot of support at the network, so the final decision only came now, almost two months after Manhattan wrapped its Season 2 run, following multiple conversations with the show’s producers. The series’ second season, which was trimmed from 13 episodes to 10, had a major new cast addition in William Petersen, who returned to television for his first series gig since CSI.

“After careful consideration, we have reached the very difficult decision not to move forward with a third season of Manhattan,” said Matt Cherniss, President and General Manager, WGN America and Tribune Studios. “We are proud of this critically acclaimed series, an extraordinary original drama, and are deeply disappointed that such a wonderful show could not find a larger audience. We thank the immensely talented (creator/executive producer) Sam Shaw and (director/executive producer) Thomas Schlamme, along with the exceptional cast and crew and our great partners at Lionsgate and Skydance, for crafting a masterful series. We are equally grateful to the dedicated fans for their support over the last two seasons.”

In a statement, Lionsgate Television Group chairman Kevin Beggs also praised everyone involved in the series. “Sam Shaw and Tommy Schlamme gave us a tremendously powerful television series chronicling the lives of those immersed in the race to build an atomic bomb in the dog days of World War II,” he said. “Their masterful depictions of small victories, devastating betrayals, and the high price of freedom will never be forgotten — just as the monstrous power wrought by splitting the atom indelibly scarred our world forever. We are thankful to our partners at Skydance, WGN America, Tribune Entertainment, and Hulu for making the series possible and to our many fans in the U.S. and across the globe for watching along with us.”

Hulu was Manhattan’s streaming home, nabbing the SVOD rights to the series at the time of its WGNA premiere in summer 2014.

“It has been an honor to work with the exceptionally talented creative team of Manhattan, led by Tommy Schlamme, Sam Shaw and our partners at Lionsgate, WGN, Tribune and Hulu,” said Skydance Television president Marcy Ross. “Thank you to the fans of Manhattan across the globe who have supported the critically acclaimed series over the last two years.”

Manhattan was WGN America’s second original drama series after breakout Salem. The network’s third drama entry, Outsiders, is off to a promising start and looks good for a second-season renewal. Based on fast nationals, the second episode this week has held virtually its entire premiere demo audience — 96% retention in adults 25-54 — despite airing with commercials vs the ad-free debut.