"The Gunk in the Garage" presents two main departures from the traditional "Bones" episode formula. Firstly, viewers see the victim get killed in the beginning of the episode, with a full view of his face. There's a good reason for this, as the man's face is the reason he was targeted.
The second departure from the "Bones" formula is Booth's lack of involvement with the case. Ms. Julian needs Booth to sit this one out while he attends a quarterly budget review. Despite having the highest conviction rate, Booth's department also has the highest cost per conviction, and he's needed to testify and justify at the hearing. There might even be a promotion and a raise in it for him, if he can stay out of the field for one day.
With Booth chained to a desk, Sweets is partnered with newbie agent Olivia Sparling. In many ways, their dynamic is similar to the dynamic between Booth and Bones in earlier seasons. Despite disdain and conflict between them due to their very different approaches to the case at hand, there is also some serious chemistry.
The case at the center of this episode is the murder of a man in a parking garage, with a slushie cup thought to be the means of causing a massive explosion that scattered the man's remains all over the 3rd floor of the complex.
The victim is identified as Robert Carlson, but when Sweets and Sparling show up at the deceased's home to break the news to the wife, the very much alive husband pulls into the driveway. It turns out that Carlson (who was adopted) had an identical twin brother that he never knew about. The dead man was not Robert Carlson, but rather a man named Jerry Langella.
It turns out that despite never knowing one another, the twins were identical in both looks and life choices. Both men were involved in a self-actualization cult that conned them into giving up all their cash and possessions. This infuriated Carlson's wife, and she hired a hitman to take out her husband. However, the hitman got the wrong guy, and killed Langella by mistake.
With the hit still out on Carlson, the FBI works quickly to save his life. The hitman turns out to be a foreman at a construction company, and the team takes him down quickly (although Lance does get injured, leading to a great moment between him and Sparling).
With Booth and Bones comfortably together, the Sparling-Sweets pairing will likely become the centerpiece of the show's new "will they or won't they" couple drama. Can you blame Sweets for being attracted to Sparling, especially when you consider how much Daisy had hurt him in the past?