TV Tropes
"Broken Base: Series 10 saw the replacement of three cast members: Sorcha Cusack (Mrs. McCarthy), Emer Kenny (Bunty) and Jack Deam (Inspector Mallory), were respectively succeeded by Claudie Blakley (Mrs. Devine), Ruby Ray-Martinwood (Brenda Palmer) and the returning Tom Chambers as the newly-promoted Chief Inspector Sullivan. Some were charmed by the new characters and delighted at the return of Sullivan. (Mallory had proven quite a divisive character amongst fans.) Others were irritated at the loss of three of the series mainstays all at once, and did not take to the new cast. Some even view Sullivan's re-appearance as a cheap attempt to lessen the blow. And a fair number of viewers regard the romance between Sullivan and Mrs. Devine as forced, unbelievable, and distressingly chemistry-free".