Prime Video has canceled a pair of first-year series, Butterfly and Countdown.

The Amazon MGM Studios series had summer debuts and each spent a short time on Nielsens top 10 U.S. streaming charts, but neither will return for a second run. The cancellation of Butterfly, starring Daniel Dae Kim, comes about two months after it premiered as a binge release. Countdown, led by Jensen Ackles, premiered in June and had a longer rollout, wrapping its 13-episode season in early September.

Butterfly, based on a graphic novel by Arash Amel and Marguerite Bennett, is a spy thriller that stars Kim as a former U.S. intelligence agent who comes out of hiding in South Korea to help his daughter (Reina Hardesty), whos also a spy. The show spent two weeks on the Nielsen streaming charts following its Aug. 13 premiere. Countdown, from Chicago Fire co-creator Derek Haas, stars Ackles as an LAPD detective whos brought into a task force involving several agencies thats working against time to stop a potentially devastating conspiracy. Jessica Camacho, Eric Dane, Violett Beane, Uli Latukefu and Elliot Knight also star.

Like Butterfly, Countdown had a two-week run on the Nielsen streaming charts shortly after its premiere. It didnt keep up that momentum as the season continued, however.

Kim (via his 3AD company) and Ackles (through his Chaos Machine banner) both have first-look deals at Amazon MGM Studios. Ackles stars in the forthcoming Vought Rising, a prequel to The Boys.

Deadline first reported the cancellations.