David Tennant be my favorite doctor . how 's that for a starter ? Billie 's not my favorite companion -lrb- that would be Martha Jones from series 3 , though Amy Pond may well take that title -rrb- , but everybody 's love for she be easily understandable . Series 2 come out swinging . it become very clear from the very begin that this doctor be not a patient man , or forgiving . when the doctor give you ` one warn ' , you take it . `` no second chance . '' that come out quite a bit through-out Tennant 's run as the Doctor , he be a fight doctor . if you be a fan of Doctor who , you need this series . if you be not a fan , this be the most likely series to change you mind .