Any roof guys here? Cedar shake roof is leaking

if there is an obvious spot that may be letting water in then get a piece of galvinized metal to slide under and up into the leaking area of the cedar shingle, some plastic cement is ok to seal an area, roof leaks can be deiceving cuz the leak can come from an area away from where the leak is dripping from inside the home, remember water is traveling downward so the shingle layout is designed and put on the roof to allow the water to drain down, if the water is pooling up in a high runoff area like yours is then it maybe pooling and going up and finding a way in to leak, id try the plasic cement aka black roof cement, i havent roofed in the last 8 years but been involved in it for 10 plus years with my dads company, also go to a roofing supply and ask for advise, dont rely on Home depot etc etc for advise