Character mistake: When Grandad collapses, the Doc calls Morwenna's grandfather Mr. Dunwich, which is the surname of one of his patients in this episode. The grandfather has the same surname as Morwenna, which is Newcross.
On The Edge - S2-E9
Continuity mistake: When Al goes to the ship to get the explosive, his dingy is powered by a Seagull outboard. When he returns, its a Mariner.
Don't Let Go - S5-E6
Character mistake: Mr. Coley the janitor climbs up on the roof and Doc Martin follows, but on the roof he keeps calling the janitor Mr. Munston.
Visible crew/equipment: After Doctor Ellingham finds the sofa on the road, Bert shows up and sits down on it and talks. As he does, watch the side mirror when Doctor Ellingham returns to his car. When the door opens, you see the reflection of a cameraman or other crew member reflected in the mirror. (00:02:05)
Continuity mistake: Mandy goes to the surgery about her stomach upset. When she goes in and when Doc Martin is examining her she is wearing denim shorts, but when she leaves the surgery she is wearing a denim mini skirt.
On The Edge - S2-E9
Continuity mistake: The ice cream Louisa smacks Martin with moves between shots from the center of his forehead to the right side and back again, changing consistency each time.
Aromatherapy - S2-E4
Visible crew/equipment: PC Mark pulls over Caroline. When the car door opens the camera crew is briefly seen in the black car door pillar reflection. (00:28:30)
Continuity mistake: Dr. Dibbs puts a chair to block the treatment room door, then bails through the window, Doc Martin and her husband go around the house to intercept her, followed by all in the waiting room...yet, when Doc Martin returns to the treatment room to examine a patient's injured arm, the door is miraculously ajar.
Character mistake: Dr Ellingham makes two character mistakes in short succession in this episode. First, in the bedroom scene with all in attendance, he calls Mrs Dunwich 'Mrs Winchelcy'. Then, when attending to Morwenna's Grandfather William in his garden he calls him "Mr Dunwich." Apparently his character name is William Winchelcy and not William Norcross (Morwenna's surname).
