In dialogue, Gil Grissom states that 9 months have passed (within the story-universe) since the first Crime Scene Minature.
The short segment near the start, from the girl watching the television report on the death of Happy Morales, to the zoom-out on the (other) girl's eye, appears to be presented with the modified colour/reduced saturation settings used to indicate flashbacks, reverting to the normal colour palette thereafter. This suggests that these few minutes are intended to set a context and (particularly in the case of the spilled bleach) fill in story elements which occurred in parallel with the previous three episodes. The reversion to the normal palette then returns us to the present day, after the events of these three episodes.
At the beginning of this episode (S07E24), a TV News reporter is doing a story on the death of Happy Morales, who died three episodes previous to this one (S07E21).
In the pre-title sequence the news reporter mentions that the boxer was found in the pool last night, implying that this episode is set within the story universe after the "Lab Rats" bleach revelation, and possibly a parallel on going investigation that wasn't shown in the later episodes, as its unclear exactly where this episode happens chronologically with the unknown passing of time.
As Grissom is examining the victim's apartment in the beginning of the episode, he shows an action figure of Spawn. Melinda Clarke, who frequently appeared as Lady Heather, appeared in the 1998 film version of Spawn.