I was among those not impressed with Helen Raynor's Dalek two-parter from Series 3, but "The Sontraran Stratagem", the opening part to her two-part story which sees the return of classic Doctor Who villains the Sontarans, is surprisingly effective and exciting.
The episode has a nice humorous tinge to its opening scenes and it is absolutely brilliant to see the Doctor's interaction with UNIT once again. The Sontarans themselves also look quite good and their storyline is handled reasonably well.
The trailer for next week's episode left me cold and a tad bit concerned rather than excited, with another really outlandish Earth invasion sort of thing apparently slated to happen. During Pertwee's era of Earth-bound stories at least everything happened under wraps. However, considering how surprised I was with this episode, next week's could be impressive as well.
I very much enjoyed Bernard Cribbins' character again. I think I like Donna's family more than Rose's or Martha's family, although I honestly could do without Sylvia Noble (Donna's mother's) cartoonish 'comic relief', which contrasted badly with the well-delivered and occasionally clever one-liners Raynor came up with.
I doubt this story will end up not being my least favorite Sontaran story, but it's already looking like it'll finish a not so distant loser, and considering the competition from classics like "The Time Warrior" and "The Sontaran Experiment", it's not really much of an insult.
7/10 for this first part, and what a cliffhanger (I sure do miss those).