Grantchester's own Sidney Chambers is no stranger to Doctor Who. James Norton appeared in 2013 episode Cold War, when his character Onegin met an untimely end at the hands of an Ice Warrior.
Now he's coming face to face with The Doctor on home ground, as Peter Davison joins the cast of ITV's mystery drama.
Davison makes a rather fitting Grantchester debut as Geoff Towler, captain of the village cricket team...
...seeming very much at home in the cricket attire, much like his Fifth Doctor did back in the 1980s.
Towler isn't quite as loveable as the Time Lord, though. In fact, he's a force to be reckoned with. The village solicitor rules his family "with a rod of iron" and isn't afraid to tell Sidney and Geordie how to do their jobs.
Will he cause trouble for the daring duo? We're going to hazard a guess and say yes.