Unfortunately, I'm going to be pretty hard on this episode. It wasn't completely awful, but it was completely bland. On top of that, almost everything they did in this episode has already been done by this show in the past, and it didn't feel like there was even an attempt at originality going on here.

The plot: Sheldon, Leonard, and Amy run into Bob Newhart - I mean, uh, Dr. Jeffries (aka Professor Proton). Later, Jeffries asks Leonard for help on a paper he's writing, and Sheldon takes offense that he asked Leonard instead of him. In retaliation, he finds a new celebrity science friend - Bill Nye. Jeffries asks Leonard how he can put up with Sheldon being so annoying, to which Leonard replies that they're friends. In the end, Jeffries shows up to ask Sheldon his opinion about the paper, and Jeffries comes in to join Sheldon, Leonard, and Penny for a cup of tea.

The subplot involved Raj and the girls making jewelry together, while Howard interrupts to try and help them make better stuff. Raj is upset because he feels he needs the space where he can talk about his feelings with the girls, and he resents Howard showing up. Howard apologizes, and Raj patches up their friendship by making them each a lightsaber belt.

So, I'm going to make a list of things this episode did that have already been done numerous times by the show. Here we go:

- Cheap excuses for celebrity cameos. It's always cool to see some of these people, but the Bill Nye one was painful, guys. The entire episode was obviously just a thinly veiled excuse for Newhart and Nye to guest star.

- Raj is girly. Okay, so he likes to gossip and talk about girl stuff. Endlessly hilarious.

- Raj and Howard and their homoerotic subtext. Getting tired of this one, especially since it came down to a very bland penis joke in this particular episode.

- A serious conversation taking place between Raj and Howard where one of them apologizes for a problem in their relationship. It's getting old.

- Penny isn't very smart! Oh, silly Penny, you don't know how to use glue! This was just painful. In fact, isn't there an episode at some point earlier in this show where she makes a whole bunch of hair clips with the guys? Shouldn't she be a glue expert by now?

- Sheldon harasses a celebrity and gets a restraining order placed against him, or otherwise makes a celebrity uncomfortable. We've seen this numerous times before.

- Leonard has to put up with Sheldon's crap, but he's willing because of the power of friendship blah blah blah.

There are other examples I could get into, but I'll stop there. There were only two things that I thought worked okay in this episode. The first is the moment at the end when Bob Newhart shows up and asks Sheldon for his opinion on the paper. This was a sweet moment of reconciliation, wherein Newhart's character recognized that Sheldon was doing the best he could with social situations, and Sheldon paid a humble and sincere compliment to one of his childhood heroes. The other thing was just Newhart in general. His acting is pretty spectacular in this, and I think only his delivery stopped me from getting tired of all the "I'm old" jokes.

I guess I'll leave it at that. In all, not a strong one. It was so forgettable that I had to go back and read through my notes more than once to even remember what had happened. Here's hoping for better in the future.