According to Deadline Hollywood . . . [Paget] Brewster just closed a deal to return to the veteran CBS crime drama, and she will be in almost every episode next season.
It goes on to say . . . Brewster's pact is for "10 out of 13", which means that, extrapolated over the 22-episode season, she will be in the majority of episodes. The actress had been approached to continue as a regular on the show but for a reduced number of episodes; now the reduction seems to be pretty small.
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Now they didn't teach us ratios in math class in medieval England, but we believe that if we extrapolate 10 episodes out of 13 episodes to the 22 episode season, it means that Paget will likely be in 17 (or 16.9230769) of those 22 episodes.