TV THIS WEEK: Amy Acker joins S.H.I.E.L.D., Archer's finale + more!

It's time for another fan-favorite Whedonverse star to join Agents of S.H.I.E.L.D.

Former Angel star Amy Acker will guest-star on the series this Tuesday as the show hopes to build more momentum leading into its vital final episodes. Meanwhile, Archer ends its daring fifth season tonight, Warehouse 13 continues its march toward the end, Game of Thrones continues to evolve in the wake of the Purple Wedding, and Arrow just keeps getting crazier. Plus, a From Dusk Till Dawn marathon, a secret exposed on The Vampire Diaries, vampires exposed on Supernatural and much more!

Check out what's happening in genre TV this week below. What's on your watchlist?

Highlights of the Week

Archer (FX) Monday, 10 p.m. - "Archer Vice: Arrival/Departure"

Season finale! - Creator Adam Reed took a pretty big creative gamble with the fifth season of his animated adult comedy, taking the title character and his co-workers out of their traditional spy agency setting and into the world of drug dealing. Archer Vice, as it was dubbed, kept its edge in the humor department but explored new territory with its characters for an entire season. Now the gamble of a season is ending, and while viewership of the series slipped a bit from last season, the show's new direction was strong enough to earn Archer a two-season renewal from FX. So what's next for the series? Well, while the ISIS/Vice team will certainly have their lives changed by the arrival of Lana's baby (which should happen tonight!), Reed has also promised the show will "deboot" and get back to spy missions next season. Check out a preview for tonight's finale below.

Marvel's Agents of S.H.I.E.L.D. (ABC) Tuesday, 8 p.m. - "The Only Light in the Darkness"

Agents of S.H.I.E.L.D. got some good news last week. After series-low ratings for its Captain America: The Winter Soldier tie-in episode, "Turn, Turn, Turn," the next episode -- "Providence" -- got a nice boost, and now the show is hoping to ride that momentum into the rest of its "Uprising" event. This week's episode could be a particularly important hinge point, too, as it brings Joss Whedon favorite Amy Acker (AngelPerson of Interest) into the fold as the cellist from Coulson's past who meets the team as Coulson fights to protect her. Meanwhile, Ward has infiltrated the secret S.H.I.E.L.D. base, and it's only a matter of time before his true nature is revealed. The show's strongest storyline thus far stands to get even stronger with the arrival of a fan-favorite guest star and what could be an absolutely devastating villain reveal. The stakes are rising week after week, and we've already got the promise of more guest appearances from Cobie Smulders as Maria Hill and Samuel L. Jackson as Nick Fury. The show is definitely pushing hard for the biggest audience possible as we head into May Sweeps, but even if the show is stronger, the same question is still lingering: Will viewers care enough to show up? Check out a preview for "The Only Light in the Darkness" below.

Arrow (The CW) Wednesday, 8 p.m. - "Seeing Red"

Arrow just keeps pushing itself further into crazy comic-book territory, and if you're really into this show's style, it's definitely an exciting time to be watching. Last week, Slade got hold of Roy and injected him with mirakuru, then managed to revive Isabel Rochev after she took two gunshots to the torso, setting up what looks like a big supervillain reveal for her. Plus, there was a Doctor Light reference, and plenty of setup for the Flash spinoff series. There's a lot going on here, and even if you're not sure about the CW-style delivery system of it all, it's hard not to admire the show for this level of comics-inspired ambition. So, how crazy will it get before the season finale? It's hard to say, but the show's definitely not slowing down. This week, Ollie and friends will have to deal with a mirakuru-infected Roy as he goes crazy on Starling City. Check out a preview below.

Orphan Black (BBC America) Saturday, 9 p.m. - "Governed by Sound Reason and True Religion"

Expectations can often be a burden for storytellers, especially when they're working on one of the most acclaimed TV series of the last year. Orphan Black earned major critical praise and a very devoted fan following with its first season, and if you were online at all last week you no doubt saw at least a small part of the massive wave of anticipation preceding the season-two premiere. But what if that anticipation backfired? What if season one of the show turned out to be a glorious flash of brilliance, and what followed couldn't possibly live up to it? It's happened before, after all. Well, if you saw the Internet's reaction after Saturday's premiere, you're aware that it didn't happen to Orphan Black. The season-two debut was met with yet another wave of acclaim as the show followed up the shockers of the season-one finale with even more shockers and set the stage for even bigger things to come. Orphan Black seems to have successfully avoided the sophomore slump for the moment. Now, with the season underway, we have to see if the fever pitch of fan excitement can be sustained. This week, Sarah is shocked by new developments in her search for Kira, Alison deals with Aynsley's death, and Cosima's sickness gets worse. Check out a preview below.

Game of Thrones (HBO) Sunday, 9 p.m. - "Oathkeeper"

After the shocking "Purple Wedding" in episode two of this season, many Game of Thrones fans were elated, but we were also left with a concern: How would the show fill the void left by one of its most compelling and unpredictable characters? Last night, we didn't get all our answers, but we got enough to keep us watching. In the wake of the Purple Wedding, things change (in a deeply upsetting way in one particular scene) for the entire Lannister family, Tyrion is in chains, and Sansa is spirited out of the capitol. Elsewhere, Jon is still fighting to prove his loyalty to the Night's Watch, and Daenerys is undertaking a new conquest. Last night's episode, "Breaker of Chains," certainly left us with plenty to chew over, set a new and frightening status quo in King's Landing and further cemented Dany as someone on a relentless mission. Now, consequences will come, as Jaime must face his actions, Jon must fight for respect again, and Dany must learn to lead in a new city. It's an exciting time to be watching the show, with so many characters moving into new, often even harsher, realities, but now comes the tricky part: Making all of these new storylines worth our time. Check out a preview for "Oathkeeper" (fans of the books know why that name is important) below:

Monday, April 21

Star-Crossed (The CW) 8 p.m. - "What Storm Is This That Blows So"

Julia asks Emery for help, Taylor and Drake's relationship is threatened by blackmail, and a hurricane traps everyone in the school. 

The Tomorrow People (The CW) 9 p.m. - "A Sort of Homecoming"

Stephen fights to destroy the Founder's machine, while Russell grows more disillusioned about the Refuge.

Metal Hurlant Chronicles (Syfy) 8 p.m. & 8:30 p.m. - "Master of Destiny" and "Whiskey in the Jar"

A warrior searches for an alien race that supposedly knows when and how every human will die. A sheriff tells a visitor about a doctor with a special talent for saving lives. Check out a new full season trailer from Syfy below.

Warehouse 13 (Syfy) 9 p.m. - "Secret Services"

Pete and Myka investigate a series of drownings that occured on dry land. Artie takes Claudia back into his memories of her sister. Here's a sneak peek. 

Tuesday, April 22

The Originals (The CW) 8 p.m. - "An Unblinking Death"

Hayley learns a new piece of family history, while Cami's efforts to help Kieran turn violent. 

Supernatural (The CW) 9 p.m. - "Alex Annie Alexis Ann"

Sam and Dean get a call from Sheriff Mills to help with a vampire threat.

Face Off (Syfy) 9 p.m. - "Heavenly Bodies"

Season finale! - The final three artists face off as they each create two alien creatures that must perform a dance routine together. Here's a sneak peek.

Jim Henson's Creature Shop Challenge (Syfy) 10 p.m. - "Life in Motion"

The designers craft larger-than-life creatures featuring realistic movement. 

Wednesday, April 23

The 100 (The CW) 9 p.m. - "His Sister's Keeper"

Bellamy leads a search party into frightening Grounder territory to find Octavia. 

Thursday, April 24

The Vampire Diaries (The CW) 8 p.m. - "Man on Fire"

The truth about who killed Maggie is revealed. Stefan tries to distract Elena. 

Friday, April 25

Grimm (NBC) 9 p.m. - "Nobody Knows the Trubel I've Seen"

When a woman on the run begins killing Wesen, Nick and Hank investigate, and find she's more than just a killer. 

Continuum (Syfy) 10 p.m. - "A Minute Changes Everything"

Alex makes a new ally. Keira helps a student who's fallen victim to a police coverup.

Saturday, April 26

The Real History of Science Fiction (BBC America) 10 p.m. - "Space"

Sci-fi creators and stars gather to discuss depictions of space in science fiction from Alien to Star Wars

Da Vinci's Demons (Starz) 9 p.m. - "The Rope of the Dead"

Leonard and Riario face a challenge in the Vault of Heaven, Lorenzo is roped into King Ferrante's games, Lucrezia encounters the Turk.

Sunday, April 27

Once Upon a Time (ABC) 8 p.m. - "A Curious Thing"

As the Wicked Witch's plan moves forward, the only way to stop her may be an unthinkable sacrifice. 

Resurrection (ABC) 9 p.m. - "Schemes of the Devil"

As Rachael's situation grows more desperate, Tom enlists help to search for her. Maggie and Dr. Ward may be on the edge of a breakthrough.

Believe (NBC) 9 p.m. - "Together"

Winter fears that Skouras may have gained the ability to track down Bo, who puts herself at risk to help someone else. 

Cosmos: A Spacetime Odyssey (FOX) 9 p.m. - "Sisters of the Sun" 

Neil deGrasse Tyson explores the lives and deaths of stars, and visits the lives and scientific contributions of female astronomers -- including Annie Jump Cannon and Cecilia Payne -- who helped shape our understanding of stars. 

Salem (WGN America) 10 p.m. - "The Stone Child"

As the fear of witches rises, John investigates what's really going on in Salem, while Mary prepares a plan. Check out a trailer for Salem's full season below.

From Dusk Till Dawn: The Series (El Rey) 12 p.m. - 6 p.m. - Season One Catch-up Marathon

It's catch-up time!: If you still haven't had a chance to catch the TV version of Robert Rodriguez's From Dusk Till Dawn, you're in luck. The El Rey Network will air the first six episodes of the series in a marathon starting at noon, then re-air them beginning at 6 p.m. So, if you're curious, and you get the El Rey Network, go set your DVR. 

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