Some casting announcements are praised, some are criticized, but they all paint a picture of a show that you can't visualize from a casting description alone. Three buzzed-about projects added a handful of new actors to their ensembles this past week, proving the networks' excitement might be warranted,

Goran Visnjic and Grace Gummer in Extant - CBS (PARA)

(PARA)

Last summer CBS decided to venture outside of its comfort zone and launch a splashy new series. Under the Dome was a massive success, so naturally the network decided to double-down in 2014 and order a second big-money series with equally big-name pedigree. The show is Extant, which is executive produced by Steven Spielberg and will air Wednesdays on CBS this summer. Halle Berry headlines as an astronaut who returns home after a year in space and realizes her experiences could very well have a major impact on the future of human events.

Joining Berry is The Practice's Camryn Manheim, Revenge's Hiroyuki Sanada, and respected Hollywood journeyman Michael O'Neill (The West Wing, The Unit). That's already a pretty formidable cast, but now CBS has added two more notable names -- E.R.'s Goran Visnjic and The Newsroom's Grace Gummer. Visnjic will play Berry's husband and Gummer will play one of his work associates.

Impact on network

This one's simple. This is a list of names that will certainly appeal to viewers. Overall, Extant is shaping up to be one of the summer's marquee new series and paired with Dome's return could mean big business for CBS. The network is working hard to own the summer.

Jeff Hephner and Mike Colter in Agent X - TNT (a subsidiary of Time Warner (TWX))

Jeff Hephner in 'Boss' (Credit: Starz)

TNT signing Sharon Stone to a new pilot deal the other week was a coup, but the names populating the cast around her are proving to be equally interesting. The drama pilot, Agent X, centers on a woman who unexpectedly becomes vice president of the United States and then learns the position carries with it the clandestine task of overseeing "Agent X," a man charged with protecting the Constitution at any cost.

In addition to Stone, producers have tabbed two "that-guy" actors for key roles -- you might not recognize the names, but odds are you've seen them before. Playing Agent X will be Jeff Hephner, who's been in the ensemble of high-profile shows like The O.C. and Boss, and currently as a recurring character on NBC's Chicago Fire, as well as one-and-done roles in Hellcats, Mercy, and The Jury. Incidentally, Hephner was originally cast in NBC's failed drama The Playboy Club, but was cut -- and dodged a bullet -- in favor of Eddie Ciboria.

X will also star Mike Colter, best known as drug kingpin Lemond Bishop on CBS' The Good Wife in addition to having roles on American Horror Story and The Following. Colter will play the Speaker of the House, who has oversight on the project and is one of the few aware it exists.

Impact on network

Both actors are one role away from breaking out, and could thrive if the show is picked up. TNT has a solid history of launching dramas and has lately become enthralled with finding another major high-profile action series instead of its trademark crime procedurals. This is shaping up to be a well-casted ensemble that shows the network's faith in the project. With The Last Ship and Legends on the network's slate for 2014, TNT's lineup of rookies is one to watch.

Stephen Root in Turn - AMC (AMCX -1.32%))

Stephen Root with Timothy Olyphant on "Justified" (Credit: FX)

AMC last weekend scored Jonathan Banks to join its Breaking Bad spin-off Better Call Saul, and it's kept the big-name castings coming. TV veteran Stephen Root, who starred on NBC's Newsradio and recurs on FX's Justified, will join Turn, the network's first of three new original drams due in 2014. Root will play Nathaniel Sackett, a member of the Committee to Detect and Defeat Conspiracies, a group that helps establish the first American spy group, The Culper Ring. Jaime Bell headlines the series, which also just cast Ian Kahn (Dawson's Creek, The Unusuals) as George Washington.

Impact on network

Root may be well known for a multitude of roles, but he has a legion of fans from his turn as Milton in the cult comedy classic Office Space. While he's known primarily for his comedy work, he also has several notable dramatic roles in HBO's Boardwalk Empire and The Newsroom to his name. Regardless, he's a face people recognize and on a new show with a cast of mostly lesser-known stars, that's a big boost. He'll bring some familiarity and stability to the series, which is critical in its early days. It's important AMC get Turn off to a good start and help set the pace for the rest of the year.