Here's where the drama really picks up. Fake Russell aka Ryan arrives home to find Jennifer heading straight for the grave where he buried the witness. He sneaks up and clocks her hard on the head, carries her upstairs, and drugs her. Jennifer then foolishly calls him out for not being her husband, so he chains her to the bed. To sum it up: she didn't play it cool.
Ryan goes out for errands for the third time. Confirmed, the guy LOVES errands. Jennifer escapes from the bedroom AGAIN by brutally ripping her foot out of the chains and resorting to her trusty bobby pin.
Clearly, the bobby pin is the real (and only) hero of this movie.
Now free, she duct tapes her foot for reasons unknown and hobbles to the garage. Lo and behold, she finds her old cell phone just in time for Ryan to come home. We then see the rotting corpse of Jennifer's f*cking husband — aka the REAL Russell — in the trunk of the car. Rough.
That's when Detective Frank arrives, and Jennifer is doing everything in her power to get his attention. And what do you know? Ryan clocks him in the back of the head, too, and dumps him in a freezer. He is one sneaky bastard.
After tying up Jennifer (with a rope this time!), Ryan nonchalantly confesses to murdering everyone in Jennifer's life, including her husband, and yeah, Jennifer takes it as well as you'd expect. (Spoiler alert: not well.)