You don't go into "Night at the Museum: Secret of the Tomb" expecting great art. You expect a few laughs and some moments of wonder as you witness museum displays magically come to life. The first "Night at the Museum" disappointed me. The second, "Night at the Museum: Battle of the Smithsonian" surprised me with how much better it was than the first. Amy Adams was wonderful as Amelia Earhart in that film.
This new, third installment, "Night at the Museum: Secret of the Tomb" was only okay, but it wasn't horrible, either. I really, really wish it had been a bit better. It's one of Robin Williams' and Mickey Rooney's last movies. Both died this year. Robin Williams does look visibly tired and sad.
One of my favorite stars makes an unbilled cameo appearance, but it is more awkward than special. Dick Van Dyke, who is a national treasure, is in the film, but only for a few minutes, and he isn't given much to do. Ditto Ben Kingsley as a pharaoh. If I were a director, I'd want to milk Sir Ben Kingsley as a pharaoh for all it was worth. Not here. Dan Stevens, formerly of Downton Abbey, is charismatic and impressive as Sir Lancelot, but his character is demoted from good guy to bad guy, and his face is disfigured, in a way that feels envious. It's as if the movie is punishing him for being a tall, gorgeous, heroic white male. Museum night guard Ben Stiller's relationship with his now teenage son is emphasized, and it doesn't feel real at all.
My two favorite scenes involved Luke Wilson as a miniature cowboy and Steve Coogan as a miniature Roman soldier. In one scene these tiny people try to comment on a youtube cat video. In another scene they are saved at the last minute from an exploding volcano.
In terms of plot or special effects magic, "Secret of the Tomb" doesn't offer anything that you can't get from the two previous films. There are no moments where you say, "Wow, I am really glad that they made this movie, so that we could see *this.*"
Even so, I mildly enjoyed the movie. If you are looking for a mindless, family-friendly good time, "Night at the Museum: Secret of the Tomb" may serve your needs.