The mysterious man on the phone was noticeably missing from The Bridge this week. Was it because he was too busy following Gina and the police investigation? Or is he someone else and plotting his own next move?

In "ID," Gina wasn't able to tell Sonya who killed her father, but the clues are beginning to pile up. Most of the hour was spent learning more about the three lead investigators of the case: Sonya, Marco, and Frye. They are each from various organizations with different motivations for finding the killer, but they are all determined to find him.

After a few teases about Sonya's past, the reason she became a police officer and is so close to Hank was finally revealed. Her sister's death was much more brutal than previously hinted at and the aftermath of that investigation hit Hank hard. After a 15-year old Sonya was forced to identify her raped and beaten sister's body, Hank took it upon himself to help her.

He didn't struggle with his decision to shoot and disable the suspect, but he did feel remorse over having Sonya identify her sister's body. The parallels between Gina's life and Sonya's should have been something they could have bonded over. If Sonya shared her story with Gina, would the result have been different? Would Gina have opened up and remembered more about what happened?

We'll never know, since Sonya wasn't able to bond with Gina. Instead, Gina ran and was killed by the beast who killed her father. Gina's death put Sonya back in her past to when her sister was killed. To cope with it, she went and visited the now mentally challenged prisoner. His drawings were creepy. The visit showed a new side to Sonya; she showed emotion and cried. It was a touching moment to see Sonya in that situation. The normally rigid and socially awkward police officer was gone and sitting there was a woman in mourning.

Sonya wasn't the only one dealing with his past, so was Marco though for an entirely different reason. His son confronted him about cheating on his wife and how it was happening again. What happened the first time wasn't clear, but Marco was adamant that it was not the same thing this time. 

Marco went home to his wife, but she didn't want to talk to him at all. She pushed him away. That wasn't the intriguing interaction though. While home, Marco grabbed a suitcase, but it wasn't for his clothes. He carried those out by hand. The suitcase was full of money and he took it to Fausto. Their relationship is a long-standing one as their fathers formed the business together.

Fausto stuck with the family business and Marco went the opposite direction to become a police officer. Is Marco a corrupt cop? Everything points to him being clean. He didn't take money to allow Charlotte and her husband to cross the bridge and he returned a ton of money to Fausto. Though, according to Frye it appears that Marco covered up the Murder House for Fausto. 

I'm not sure if Marco did that or not, but if he did it was for the right reasons. Marco may have been hamstrung at his job, but covering up something of that magnitude would take a lot for him to do. With Frye sobered up, he will be a force to reckon with in the investigation. He's not going to let it go.

Sonya and Marco should use him as a resource to get information that they can't get. He can go places and do things that they can't. Plus, for some reason the killer has drawn Frye into the mess. He's the only target who has made it out alive.

The Charlotte storyline continued to be the weakest of the bunch. At some point, I expect that the tunnel will become an issue in the murder cases, but for now I don't really care much about her, Ray or the tunnel. 

The main investigation turned up several important clues in "ID," including that the killer is most likely law enforcement or close to the investigation. He knows what's going on and knew the police had Gina. He also had a fake cop car that he used. Gina did provide a partial description. It's not enough to find the guy, but if they get close to him perhaps it will help confirm his identity.

The big question still remains unresolved: Are the Beast and the Man on the Phone the same person? I still believe they are two different people. The Man on the Phone is reacting to the Beast's killings and other wrongs across the borders.

Which main character do you find the most compelling at this point? Will the police or Frye find the killer first? Is the Beast also the Man on the Phone?

Carla Day is a staff writer for TV Fanatic. Follow her on Twitter and on Google+.