Few were surprised when Sherlock stars Benedict Cumberbatch and Martin Freeman hinted Season 4 would be the last, but the reason may go deeper than exhaustion or busy careers. Freeman says he’s not eager to go back after Season 4, as “some of it’s not fun anymore.”

The fourth season ended on a conclusive note in January 2017, and Cumberbatch and Freeman have since concentrated on their Marvel roles as the title hero of Doctor Strange, and Black Panther’s Everett Ross. It’s too early to think about any fifth series of the fan-favorite BBC procedural, but Freeman now tells The Telegraph that playing Dr. John Watson has more or less lost its appeal. High expectations from fans led to mixed reception of the fourth season, and Freeman says the process has become demoralizing (h/t Entertainment Weekly):

I think after series four [it] felt like a pause. I think we felt we’d done it for a bit now. And part of it, speaking for myself is [due to] the reception of it. To be absolutely honest, it [was] kind of impossible. Sherlock became the animal that it became immediately. Whereas even with [the U.K. version of] The Office, it was a slow burn. But Sherlock was frankly notably high quality from the outset. And when you start [that high] it’s pretty hard to maintain that.

Being in that show, it is a mini-Beatles thing. People’s expectations, some of it’s not fun anymore. It’s not a thing to be enjoyed, it’s a thing of: ‘You better f—ing do this, otherwise, you’re a c—.’ That’s not fun anymore.

Last we heard, Sherlock creator Steven Moffat was comfortable leaving the series behind, and has since moved on to a new Dracula project with writer Mark Gatiss. Cumberbatch had also suggested Season 4 might end the series, though Gatiss expressed in interest in returning when the two stars reach the age of famous Sherlock actors Basil Rathbone and Nigel Bruce.

We’ll keep hope alive, so stay tuned for Sherlock news in the meantime.

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