Final answer:
Lockstock's description of the Act One finale would typically refer to the climax of the story, but without the specific play or musical context, it's not possible to accurately choose an event from the options provided.
Step-by-step explanation:
The event that Lockstock describes as the Act One finale in the context of a musical or play typically would be the climax, which is the peak of the action. However, without the context of which particular play or musical this question is referring to, it's challenging to determine the specific events such as an uprising, musical rehearsal, or Bobby's arrival. In general, events like the assassination of a leader or a takeover could be considered significant enough to qualify as a climactic end to an act. The event that Lockstock describes as the Act One finale is None of the above. In the context of a theatrical performance, the Act One finale is typically a climactic moment or a song that leaves the audience on a high note before the intermission. It serves to engage and captivate the audience, building anticipation for the remainder of the show.