When we last left team Sanctuary — always battling the world’s “abnormals” — its members were fighting a giant spider named Big Bertha. In the first of season three’s generous 20 episodes, they’re still trying to undo the arachnid’s anarchy, namely in the form of tidal waves. Once that’s foiled, it’s time for a new near-season-long arc, which entails team leader Dr. Helen Magnus (Amanda Tapping, TV’s “Stargate: Atlantis”) and Nikola Tesla (Johnathon Young, “The Fog”) attempting to track her father to Hollow Earth, which is just what it sounds like.

As always, the stand-alone plots interest me more than digging deep into its own mythology. With impressive special effects for a Canadian production that is heavily reliant on green screens, highlights among these hours include:

• “Bank Job,” involving a heist where a very hungry bug is seeking hosts. Lots of urinating and retching in this one.

• “Hero II: Broken Arrow,” a gender-flipped redo of last season’s episode about a shape-shifting superhero suit that turns wearers evil. The jabs at marketing are appreciated, but since “Sanctuary” has already done this story (as has the aforementioned, superior “Warehouse 13”), why again?

• “Animus,” a werewolf episode not as good as those done by “True Blood” or “Being Human” (the BBC version). Parts of this one are even tinted in shades of “Underworld” Blue.

• “Breach” gives Tapping almost a show of her own as she’s forced to play tag with a hooded, materializing menace in an abandoned building. His identity? Spoiler alert: Jekyll.

• “Metamorphosis” puts one-time second star Robin Dunne (“Species III”) front and center, as he awakes to find himself slowly turning into a lizard. A more literal Kafka adaptation would have been nice, but at least the scales allows for a less-than-sympathetic co-worker to ask, “Any way you can save us 15 percent or more on car insurance?”

As was a problem for me with the sophomore season, this junior batch still suffers immensely from the absence of Emilie Ullerup (“Hunt to Kill”) as Magnus’ daughter. The show hasn’t been the same without her, which is to say, since year one. Her replacement of Agam Darshi simply pales. Still, Magnus herself is a fiercely strong character able to command viewers’ attention.

While I’ve praised the packaging for previous season sets, eOne may have dropped the ball this time, as half the discs sit directly on top of the others. I’m sure that’s a cost-cutting measure, but it can’t good for the life of the discs; they may get scratched simply by trying to remove them. —Rod Lott