So did Rennie know after receiving the Black Widow as a gift by Jessie that she was onto her or after her? They have this subtle conversation about it "not being over yet" and Rennie saying it's impossible to know if she loves or not etc.
Y'know, I could eat a peach for hours
I think Rennie figures out there's something up with Alex/Jessica when they're in the market, and Alex is talking to Shin. The shots of Rennie suggests she's getting suspicious. Then she calls Sara and asks if anyone's been asking about her. When Sara tells her that she had been visited by a woman from the Federal Government, Rennie figures out that this Jessica Bates person must be an investigator of some sort.
shareI think Rennie kind of liked Alex, and was angry that she wasn't who she said she was (probably the reason she placed the pillow and punched herself). Funny; she met someone like herself: someone who was pretending to be something else.
shareyes im sure she knew what was up long before that
shareThis always gets me also but as you say, I think she at least suspected something early on right back to when she called her friend and was told a woman had been asking questions about her.
It has to be tense to appease the audience and keep them guessing. For example, when the two ladies were diving, Alex ran out of juice and for a while we thought Rennie was going to let her die. Had she tampered with the tank? Was she originally intent on killing her off and then changed her mind? Was she reluctant to implicate herself but wanted to put the frighteners on Alex in a subtle way not to mess with her? There are so many what if's!!
"Has anyone seen my wife?" - Columbo