TV THIS WEEK: Warehouse 13 premieres season 4.5, Grimm and more!

warehouse 13

While many of the continuing series build toward the end of their seasons, Warehouse 13 returns with the second half of season four, and Merlin returns with the final four episodes of the series. We'll also get a big move when Grimm moves to Tuesdays.

Also this week, Nolan and the town face Hellbugs on Defiance, Miles and Monroe go home on Revolution, Norma gets her first motel guest on Bates Motel, William Shatner hosts a new reality series called Weird or What?, Malcolm's plans for the Glades are explored on Arrow, Kevin sends a video message to Sam and Dean on Supernatural, Bob Newhart guest-stars on The Big Bang Theory, Damon and Stefan try to torture Elena into getting her humanity back on The Vampire Diaries, Vincent gets jealous on Beauty & The Beast, Amy Acker returns on Person of Interest, Moriarty plagues Sherlock once again on Elementary, Eddie Izzard guests on Hannibal, the truth comes out on Touch, Leonardo unveils a new weapon on Da Vinci's Demons, Diana Rigg gets evil on Doctor Who, Sarah goes to the suburbs on Orphan Black, it's evil vs. evil on Once Upon a Time, and a lot of stuff happens to a lot of people on Game of Thrones.

Here's what we have to look forward to this week on sci-fi, fantasy and paranormal TV.

Monday, April 29

Defiance (Syfy) 9 p.m. - “The Devil in the Dark”

Defiance faces an invasion of Hellbugs. Meanwhile, Irisa begins to have disturbing visions.

Here's a promo:

Revolution (NBC) 10 p.m. - “Home”

Monroe and Miles end up in their hometown as things get personal. Meanwhile, Aaron runs into someone he has a history with while on his trek with Rachel to the Tower.

Here's a look:

Bates Motel (A&E) 10 p.m. - “The Man in Number 9”

Norma gets her first guest at the motel. You've got to figure if Norma wants to make a living, all the guests at the Bates Motel can't end up as psychos or murder victims, can they? Meanwhile, Norman tries to figure out women.

Here's a promo:

Warehouse 13 (Syfy) 10 p.m. - “The Living and the Dead”

Season 4.5 premiere! Last season Artie became the Big Bad and set loose the Black Orchid's “Sweating Sickness” on the world. Bad Artie! Now the race is on for the team to reverse what could be the deadliest pandemic since the Dark Ages. Guest stars this season include Buffy's James Marsters, Caprica's Polly Walker and X2's Kelly Hu.

Here's a look:

Tuesday, April 30

Grimm (NBC) 10 p.m. - “Endangered”

New time! New day! Grimm moves to Tuesdays to help NBC fill the timeslot, and the move might just be an advantage, considering it's after The Voice and all. In the episode, cow mutations and glowing creatures make Nick suspect Wesen aliens might be at work. Meanwhile, Nick learns more about the key and Juliette begins to put two and two together. Seriously, what's Nick's excuse for not just spilling the Grimm beans with his lady love at this point?

Here's a sneak peek:

Weird or What? (Syfy) 8 & 9 p.m. - “Alien Encounters” and “Life After Death”

Series premiere! It appears host William Shatner's going to play it a little loopy in this new reality series, which looks at three separate stories of the bizarre and unexplained to weigh the various supernatural and scientific theories behind the subject. In the first two episodes, alien encounters and life after death are explored. Ten episodes have been ordered.

Here's a promo:

Wednesday, May 1

Arrow (The CW) 8 p.m. - “The Undertaking”

Looks like we'll get the scoop on the Undertaking in this episode, as well as a clue that might help locate Walter. Meanwhile, Malcolm spills about his wife's murder and how that shaped his plans for the Glades.

Here's a preview:

Supernatural (The CW) 9 p.m. - “The Great Escapist”

Sam and Dean get a video message from Kevin Tran, which leads them to go after the Third Trial. Elsewhere, Crowley hits a winning streak, while Castiel is hunted by Naomi and the angels.

Here's a look:

Haunted Collector (Syfy) 9 p.m. - “Lakeside Terror; Pythian Secrets”

John and his team investigate an inn in Arkansas and a castle in Missouri.

Here's a promo:

Deep South Paranormal (Syfy) 10 p.m. - “Old Soldiers Never Die”

The team looks into the site of a Civil War re-enactment.

Here's a preview:

Thursday, May 2

The Big Bang Theory (CBS) 8 p.m. - “The Proton Resurgence

Bob Newhart alert! Sheldon is thrilled when he hires the host of his favorite childhood TV program, Professor Proton (Newhart), to appear in his apartment. Meanwhile, Howard and Bernadette dog sit Raj's dog.

The Vampire Diaries (The CW) 8 p.m. - “She's Come Undone

Damon and Stefan decide to do whatever it takes to get back the girl that they love. Elsewhere, Caroline has a run-in with Klaus and Bonnie is suspicious when Katherine makes her a supposedly mutually beneficial offer.

Here's a preview:

Beauty & the Beast (The CW) 9 p.m. - “Anniversary

Vincent's suspicions grow when it comes to Gabe, who he believes may be involved with a sniper who tried to kill the mayor. Meanwhile, Cat discovers evidence that her mother may still be alive.

Here's a promo:

Person of Interest (CBS) 9 p.m. - “Zero Day

Amy Acker alert! When the Machine starts spitting out erratic numbers, Reese and Finch find themselves facing Root (Acker) once again. Meanwhile, the hunt is on for an elusive tech millionaire, and Detective Carter tries to take down Cal Beecher's killer.

Here's a preview:

Elementary (CBS) 10 p.m. - “A Landmark Story

The search for Moriarty continues when Sebastian Moran tells Sherlock that the evil mastermind might be responsible for recent murders.

Here's a look:

Hannibal (NBC) 10 p.m. - “Entrée

Eddie Izzard alert! Izzard gets his creepy on playing a murderer who may be the Chesapeake Ripper, or not. Will and Jack investigate, but the case takes its toll on Jack, who reaches out to Hannibal for help.

Here's a look:

Friday, May 3

Touch (NBC) 9 p.m. - “Fight or Flight”

“The truth is exposed,” promises the promo below, which is a good thing for fans, considering how low-rated Touch is. In the penultimate episode, the study of the 36 makes Aster Corps execs nervous, which puts pressure on Calvin to come up with the results they want.

Here's a promo:

Merlin (Syfy) 10 p.m. - “With All My Heart”

The final season returns! Merlin risks everything to end Morgana's control over Gwen, and Arthur goes against everything he believes to save his queen. There are just four original episodes left in the series, and they'll air through May.

Here's a look:

Da Vinci's Demons (Starz) 10 p.m. - “The Magician”

Leonardo reveals his newest weapon of war when the armies of Rome and Florence prepare to clash.

Here's a preview:

Other Friday shows of interest:

On the Travel Channel's The Dead Files (10 p.m.), Steve and Amy investigate to help a family that's dealing with a haunting in Watervliet, Mich.

Saturday, May 4

Doctor Who (BBC America) 8 p.m. - “The Crimson Horror”

Diana Rigg alert! The Avengers' Diana Rigg and her real-life daughter, Rachel Stirling, appear as mother and daughter. In the episode, the Doctor and Clara investigate when bodies are found in Victorian Yorkshire that have waxy, glowing, red skin. Rigg's character, Mrs. Gillyflower, runs a mill called Sweetville, and she might not be what she seems. When the Doctor and Clara vanish, it's Vastra, Jenny and Strax to the rescue.

Here's a look:

Orphan Black (BBC America) 9 p.m. - “Variations Under Domestication”

Sarah's search for the truth is put aside when she has to take a trip to the suburbs. Meanwhile, Alison's paranoia causes trouble for all the Orphans.

Here's a preview:

Sunday, May 5

Once Upon a Time (ABC) 8 p.m. - “Second Star to the Right”

The penultimate episode of the season promises it's evil versus evil as we get the big setup for the “devastating” finale. And it looks like we're headed to Neverland.

Here's a preview:

Game of Thrones (HBO) 9 p.m. - “The Climb”

Strategic unions for the Lannisters are plotted by Tywin, Melisandre heads to the Riverlands, and Robb considers a compromise with House Frey. Meanwhile, Jon, Ygritte and the Wildings attempt a terrifying climb.

Here's a look:

What are you going to watch?

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