It’s episodes like ‘Ipsa Scientia Potestas Est’ that make it clear just how much faster than your average TV drama Orphan Black is moving.

The core of the episode is all about Helena, as she seemingly puts herself under Sarah’s protection before following her own agenda.

Rachel’s not best pleased about Helena having killed Daniel, but she’s also quick to replace him by using Paul to fill his position. Showing her ruthlessness, she then moves ahead with a two-pronged assault on Sarah, both by trying to withhold Cosima’s treatment and by framing Felix for murder. She’s also closing in on Cal, solidifying her position as Sarah’s biggest threat. Like everyone, though, she underestimates Helena. It’s a mistake that’s bound to cost someone their life before the season ends.

Helena is fascinating. She outwardly appears scatterbrained but is in complete control of almost every scenario she finds herself in. Sarah thinks she’s keeping her safe and confined by putting her under Art’s protection, but it’s not hard to see how she’ll escape the situation and get on with her own business. That business is murder and Rachel’s the target.

Under most circumstances, it’s hard to see why Sarah would care about Helena killing off the “pro-clone”, but with Felix in danger Sarah makes a heartfelt plea that her sister put down her sniper rifle. Is her cooperation a sign of the beginning of a closer sisterly bond? It seems like it might be, but it’s also difficult to tell how far either one of these characters trusts each other.

This week we don’t get to check in with Alison, hopefully she’s making progress in rehab. ‘Ipsa Scientia Potestas Est’ is a focused episode that keeps us on track with our exploration of Project Leda, and the events are mostly viewed through the eyes of Helena and Sarah, with Helena taking action and Sarah largely in a reactive role.

It’s interesting to see Paul embrace his new position and display a willingness to do things that Sarah won’t easily forgive him for. Rachel also has sex with him, a move that allows her to both exert control over him and feel as though she’s taking away something of Sarah’s. We all know she’s after Kira, and this episode at least assures us that Cal is taking care of her and has the means to keep her safe.

Perhaps most interestingly, the new Proletheans are revealed to be not quite as progressive as we thought in relation to the old faction. They may believe in scientific methods, but Henrik is still happy to sew up his daughter’s mouth when he merely suspects her of lying to him. It’s worrying stuff, as is their insistence on getting Helena back so that she can carry the child.

Chances are they’ll underestimate her and she’ll kill them with her sniper rifle, though, Helena’s quite clearly not one for playing around and everyone would do well to remember it.

Aired at 10pm on Wednesday 28 May 2014 on BBC Three.