4. T.J. Hooker(IMDB: 6.1/Rotten: NA)
Not the highest-rated series on the list and it's easily his worst showing on IMDB, but T.J. Hooker really does have something going that none of the other shows up until have; a cultural significance. Up until this point in the list, none of his other shows succeeded. So while some may have higher IMDB scores, or actually have a Rotten Tomatoes score, none of them reached 91 episodes like T.J. Hooker did.
In fact, the show is Shatner's second longest as a series. He got 91 episodes out of T.J. Hooker, which is considerably more than every other show he's ever been in but one. And no, that one isn't Star Trek.
3. For the People (IMDB: 7.7/Rotten: NA)
Even though we haven't seen For the People yet, and it only lasted for 13 episodes, fans seemed to love it. It has a 7.7 on IMDB and features a young Jessica Walter of Arrested Development and Archer fame. With a staring duo like that, the show clearly had something going for it. It was the first regular series starring the role of Shatner, as well as one of the few shows at the time that showcased the personal lives of its main characters.